S22 Ultra (used, previously opened) — signal drops to "Emergency calls only" for 2-3 sec, 5-10+ times/day, recovers on its own
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Bought a used SM-S908N (Korean variant) that was previously opened/repaired before I got it. Using it in Lebanon on Alfa's LTE network (no 5G here).
Symptoms:
- Signal randomly drops to "Emergency calls only" for 2-3 seconds, then auto-recovers
- Happens 5-10+ times a day, no pattern I can find (different locations, doesn't seem tied to movement)
- Sometimes get a popup: "Something went wrong with your network connection. Try restarting your phone, or tap here to set your roaming network"
- Already tried: locking to LTE-only (no change), cleaning/reseating the SIM (no change), reset network settings (haven't tried yet)
- Since it was previously opened, suspecting a loose antenna flex cable connector
Has anyone dealt with this exact pattern on an S22 Ultra? Trying to figure out if this is a known antenna cable issue before I take it to a repair shop — want to know what to ask them to check specifically.