So I did a fly today but I had a problem with ATC. I did a cold dark start and I think I missed something with the radios. I couldn't contact to the ATC so I didn't care at first but then while I was near to landing, FMC said ILS/freq error so its clear that its my problem. Can someone tell me what did I do wrong?

When starting from C&D you need to manually switch on your COM radio by selecting on COM1 or COM2 on the centre pedestal. Good luck!

As for the FMC ILS/freq error, when you power up the aircraft go to the CDU NAV RAD page and DELETE the ILS frequency and the two VORs frequencies. This will reset them to auto-tuning.

Normally they should have been set in auto-tuning automatically on power-up, but this a known bug when loading the C&D state which will be fixed in the next update.