I am using 4G GSM EC200U-CN and i am using the sim card JIO 5G sim and getting the error fail to register the network. The module information and sim card information is being displayed but the registration information is not being displayed.
Try with airtel simcards. I have tested with same simcard.
If it worked just click the 
for me.
Any other way,because i have jio sim card only
https://forums.quectel.com/t/jio-sim-card-not-registering-to-network-on-ec200u-cn-module/34676/9?u=sandesh_kale
Check this post once and try it.