With the S23 range being ip68 rated for water and dust, I am very surprised your phone could have allowed moisture inside from a little sweat. I mean they are designed to be resistant to water down to 1.5 metres for 30 minutes. So if it can be immersed in water for that duration, a little sweat on the outer case should have been robust enough.
With that out the way, if the phone was opened by an engineer there is always a chance that something was dislodged. Maybe completely different from the original fault, but I seem to recall there being some connectors on flexi cables for the cellular antenna that could have been accidentally affected. I know there is a fault with the S22 ultra design whereby a flexible cable needs to be replaced.
This might or might not be relevant to your situation, but worthy of note.
It sounds like you used a repair shop that is not approved by samsung, so if you did have warranty left then it is likely no longer valid unless it was repaired at samsung repair centres.
Dare I say it, but if this is a base model of S23 and being a couple of years old, it may be worth considering an upgrade. You could spend a lot more money, 'throwing good money after bad' if you like... and find that even a few hundred pounds more costs and still have a compromised phone.
The alternative is to go back to the shop you went to for the repairs and mention your discontent. I would say if they are reputable they should warrant their work for a few months !
It also may be worth considering trading it in for a newer model. I know samsung site are offering good prices (£300) for an 'S series phone in any condition' against some of the current models.
Hope one way or other you resolve your issues.
Smiley
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User: Smiley
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My life is full of positives and negatives. I’m an electrical engineer.
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