I have an iphont 4 since I activated my personal hotspot the phone keeps losing the sim card
Leave the SIM card in the phone, then it is less likely to be lost.
The sim card is in the phone but the phone sometimes can't detect the sim card
Okay... not being detected is completely different from being lost.
Remove and re-insert the SIM.
If the problem continues, get a replacement SIM from the carrier.
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