First identify whether your Galaxy A51 has no cellular service, cannot detect its SIM, or has working calls but no mobile data. Restart the phone, check SIM and carrier status, then troubleshoot data and APN settings. If those steps fail, reset mobile network settings and use Samsung Members diagnostics if available.
Identify what is failing
Check whether calls and texts work, or whether the problem is limited to internet access. “Emergency calls only” or no signal points to a cellular connection issue; “No SIM Card Detected” points to SIM recognition; calls that work while data does not suggest a data-service, coverage, or APN problem. The next checks depend on which symptom you see.
Fix no service or a SIM-not-detected message
Restart and check SIM status
Restart the phone first; a restart can clear a temporary SIM-recognition or software problem. Then open Settings > About phone > Status information > SIM card status and check whether your carrier appears under Network. Menu labels may differ with the A51’s software version.
Check activation, coverage, and carrier restrictions
Contact your carrier to verify that the line and SIM are active, that the SIM is allowed to activate in this device, and that there is no local outage or coverage problem. Some carriers use SIM-protection services that can prevent activation; Samsung notes that many SIM issues require carrier assistance. See Samsung’s SIM troubleshooting guidance.
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- Tips : NOT for Samsung Galaxy A51 5G UW A516V , NOT for Samsung Galaxy A51 5G A516 2020 , NOT for Samsung Galaxy A71 5G A716 ; NOT for Samsung Galaxy A51 4G Dual-Sim Version , NOT for Samsung Galaxy A71 4G Dual-Sim Version .
- Compatible with : Samsung Galaxy A51 4G 2019 Single-Sim Version : SM-A515F, SM-A515U , SM-A515U1, SM-A515W ; Samsung Galaxy A71 4G 2020 Single-Sim Version : SM-A715F , SM-A715U , SM-A715U1, SM-A715W .
- The item only fits for Galaxy A51 4G(or A71 4G) Single-Sim Version ; Please see carefully before ordering ; It is very very important, make sure what your device is .
- We will not be responsible for any damages to your device that you may cause during the changing of replacement parts .
- Package Content : 1 x Samsung Galaxy A51 4G Single SIM Card Tray Holder (like the Picture showing that) , 1 x Eject Pin .
Reseat and inspect the SIM
- Remove the tray carefully and check that the physical SIM is positioned correctly. Galaxy phones using a physical SIM use the Nano-SIM format.
- If the contacts look dirty, wipe them gently with a soft, dry cloth. Do not touch them with a metal object or force the card into the tray.
- Reinsert the SIM and tray fully, then check whether the phone recognizes the carrier.
A SIM ejector tool can help remove the tray, but it cannot resolve an account, carrier, or software problem.
Try another active SIM if available
If a known-working SIM is recognized, the original SIM or its account is a likely place to investigate; ask the carrier about activation or a replacement SIM. If a known-working, active SIM also fails, run the phone’s SIM diagnostic if available and consider Samsung service. That result makes device service more relevant but does not, on its own, prove a particular hardware fault.
Rank #2
- Replacement Sim Card Tray for Samsung Galaxy A51 5G version (model# SM-A516U, A516U1), Verizon A51 5G UW (SM-A516V)
- It will not be compatible with Non-5G version Galaxy A51. To ensure it's the correct part for your phone, before making the purchase, please check your phone model at: Settings --> About Phone
- Brand new. Repair replacement parts. Color: Black
- Compatible with Single Sim Card version Samsung Galaxy A51 5G phones
- Content: 1 x sim card tray; 1 x eject pin
Fix mobile data when calls still work
Confirm data service and coverage
Make sure Mobile data is enabled. Check with the carrier that your account includes active data service and ask whether coverage or network conditions in your area could be preventing access. Samsung’s guidance on internet disconnections over mobile data identifies coverage and APN settings as relevant checks; it does not provide one APN that applies to every carrier.
Get the correct APN from your carrier
An incorrect Access Point Name (APN) can stop mobile data from connecting. APN values are carrier-specific, so ask your carrier for the settings for your plan, SIM, and region rather than copying values from another network. The carrier can also confirm whether the data service is active.
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Rank #3
![[2pcs Pack] Galaxy A51 5G Replacement SIM Card Tray Holder Parts for Samsung Galaxy A51 (5G) SM-A516U SM-A516N SM-A516B -Black Color (Not fit for A51 4G A515)](https://m.media-amazon.com/images/I/41sYZ0o-OQL._SL160_.jpg)
- [Compatiable Model] Single SIM Tray Replacement Parts for Samsung Galaxy A51 (5G) SM-A516U SM-A516N SM-A516B -Black Color
- [Attention] not fit for Galaxy a51 4G A515 SIM version,you can find you phone version through: Setting-About phone-Model.
- [Need to Know] No Include Install Guild Paper,install need sure the Card Direction and suggest restart the phone after success install.
- [Package Include] 2pcs *SIM Card Tray Holder Replacement Parts (another for storage Purpose) + 1* Free Universal Usage Type Eject pin
- [Quality] Produced from a third party factory,Apperance/Color/Size being Check Strictly before Delivery
Reset mobile network settings if the checks fail
If restarting, carrier checks, and the relevant SIM or data checks have not helped, reset the mobile network settings. Verizon’s Galaxy A51 instructions and Samsung’s general guidance give this route:
- Open Settings.
- Tap General management, then Reset.
- Tap Reset mobile network settings and review the confirmation screen before proceeding.
The reset’s exact label and effects can vary by software. Verizon warns that its network reset clears or restores cellular, Wi-Fi, and Bluetooth settings, including saved networks and passwords. Read the phone’s on-screen notice so you know what will change on your device.
Rank #4
- Package includes: SIM and Memory Card Tray Holder X 1; SIM Card Ejection Pin X 1
- Compatible with: Samsung Galaxy A51 5G UW SM-A516V
- High Quality,100% Brand New.
Run diagnostics and decide when to seek service
If Samsung Members is installed, open Samsung Members > Support > Get started, then select SIM under Phone diagnostics. If the carrier confirms that the SIM is active and working but the A51 still cannot recognize it, Samsung recommends arranging service. Samsung’s Galaxy A51 support page lists materials for model SM-A515F/DSN, including manuals for different Android versions, so menu names may not match every A51 exactly.
Quick Recap
Best Value
- Tips : NOT for Samsung Galaxy A51 4G 2019 Dual-Sim Version ; NOT for Samsung Galaxy A51 4G 2019 Single-Sim Version ; NOT for Samsung Galaxy A51 5G 2020 Dual-Sim Version .
- Compatible with : Samsung Galaxy A51 5G 2020 Single-Sim Version : SM-A516F , SM-A516U , SM-A516U1 , SM-A516W , SM-A516N ; Samsung Galaxy A51 5G UW SM-A516V (Verizon) .
- The item only fits for Galaxy A51 5G Single-Sim Version ; Please see carefully before ordering ; It is very very important, make sure what your device is .
- We will not be responsible for any damages to your device that you may cause during the changing of replacement parts .
- Package Content : 1 x Samsung Galaxy A51 5G A516 Single SIM Card Tray Holder (like the Picture showing that) , 1 x Eject Pin .
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
