Why is my phone only working on cdma and not cdma/lte?

[Android Central Question]

I have a j7 sky pro from total wireless and it only works on cdma with 3g. I had 4g LTE before and it just stopped working so I switched it to cdma for now. The apn has never been changed and I double checked with the apn I found on Google for total wireless. I did a factory reset, and even turned off the phone, took the sim out, put it back in and turned the phone on. Also when I turn it back on it gives me this symbol of a padlock unlocking and I dont know what it is. Please help

 

[methodman89]

Did you enable LTE in Settings?

 

[Cody Ayers]

When I switch my network mode to CDMA/LTE it doesnt do anything. I can only use CDMA. Its only putting out 3g.

 

[Mimmzy]

That padlock symbol usually means it is an unlocked device, not sure why you are seeing it if you bought it from the carrier you are using. Have you switched carriers since purchase, or where did you get the phone from?

If you didn’t change any settings and you have factory data reset it, but it used to work there are only a few things it could be.

1.) Bad SIM card (most likely)

2.) Bad phone antenna or SIM tray connection (unlikely, it’s usually all or nothing with those kinds of hardware issues.)

3.) Your carrier’s frequencies in the area has changed (highly unlikely, seeing as it was a downgrade. Usually only disappearance of older frequencies happens as carrier upgrade towers and phase out older technology. This is usually done with a warning text or push notification of some sort.)