There are so many factors that can cause a cell phone to display Emergency Calls Only
Does this happen everywhere and is it a constant issue? If not and it only happen in specific locations then chances are this issue is due to a poor signal from your wireless network in that area and will be outside of your control.
# Change the Network Mode to GSM Only
# [https://www.ithemesforests.com/how-to-fix-a-cell-phone-that-says-emergency-calls-only/|Select your carrier manually]
# Check the position of the SIM card
Airplane mode trick
Activate the “Airplane mode” feature on your cell phone and then turn it off. Make a call and see if the phone was able to reach out, connect to the network, and make a call.