[mien]

I woke up this morning to find my phone not detecting either of my two sim cards.please help. My phone is infinix x551 16gb 1gb

[hovatek]

I woke up this morning to find my phone not detecting either of my two sim cards.please help. My phone is infinix x551 16gb 1gb

1. Check Settings > About > Baseband. 
2. Dial *#06# 
What do you see for each?

[mien]

invalid imei
invalid baseband

[hovatek]

invalid imei
invalid baseband

You'll need to reflash the firmware @ https://www.hovatek.com/forum/thread-6879.html using SP flash tool @ https://www.hovatek.com/forum/thread-159.html
once you regain baseband, fix null IMEI using https://www.hovatek.com/forum/thread-116.html