I have an Iphone X and since the latest ios 15 update my signals for phone suddenly went off and since then it’s of no use. Tried inserting the sim in other phone working perfectly and have tried resetting network and factory reset as well it is of no use. Please let us downgrade back to ios 14 or provide a solution. Sim is really important nothin Can be done with out it. I’m really sick of this bug. Missed many important meetings and calls due to this bug. Apple’s quality is deteriorating day by day. Really disappointed. Provide some solution pls??