Water damaged, No Service, IMEI & ICCID fine

Hi!

Bought an iPhone 5S a couple of days ago, that I knew was water damaged. Got it cheap so it wasn't a huge deal.

Everything is working perfect, except I am getting no service. Have been googling a lot but I cannot figure it out.

The phone has been laying in rice for over a day now, and I also tried to open the phone to see if I could see anything out of the normal.

The IMEI and ICCID info shows up, so after what I can understand the logic board should be fine.

Any help, guys?

Thanks