If anyone has any advice please let me know. I don't know what else I can do to see to remedy the problem. I was told once again to contact my old carrier to get my phone unlocked. I am still getting the invalid sim card error. My sim is working fine on another phone so cant be sim.

Last thing I did right before I got the 'Invalid SIM card/ Network locked SIM card inserted' notification was the security hack to bypass exchange thru Xtouchwiz xposed app. I signed on the technical support on the Tracfone website and was sent another sim card within 48 hours. I contacted Cricket today and they reprogramed my SIM card. Already on marshmallow, was trying out a couple of international roms which were working fine. I bought a LG L62VL a couple months ago and received an 'invalid sim card' message within a couple days. I was told to contact Cricket to reprogram my device after it was confirmed my device was unlocked from their network. After 48 hours, I was still getting the invalid sim card message. Saturday, I had contacted Virgin Mobile to put in a phone unlock request. It works in another cricket phone but won't work on my phone. Saturday I was able to replace my SIM but I'm still getting the 'invalid sim card error.' I've been going back and forth between Virgin Mobile and Cricket trying to figure out why my SIM isn't working. I went back and forth between my old carrier (Virgin Mobile), Motorola and Cricket Support. I was getting the 'Invalid sim card' issue when trying this on my Samsung A50 (not a 5g phone). After the update, my SIM Card no longer worked. If you are trying to change over from your Sprint sim to new T-Mobile sim, be aware that the new T-Mobile sim cards only work in 5g enabled phones.

About a week and a half ago, my Motorola e4 had a system update.