I have a problem with my factory unlocked iPhone 5S from UK. Today I bought a iPhone 5S that is unlocked, and I can't activate it. I tried with 2 valid / working sim cards without pin and no success. The error I got is:
- No SIM card installed.
- Insert a valid SIM with no Pin lock to activate iPhone.

I called the owner of the phone, and he told me that the prone worked perfectly before. He told me to try other sim, I tried, but the same error again. I also tried to activate it via iTunes, but I got the There is no SIM card installed in the iPhone you are attempting to activate error in iTunes. Can you tell me what to do to activate my iPhone 5S? Thanks in advance. Stephan.
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