Youshould  struggled switching the mobile phone network settings from LTE/WCDMA/GSM to Auto. We would declare attempt altering the network mode to somewhat different and then once more change back to the LTE/WCDMA/GSM mode.
Samsung Galaxy 5 not connecting to 3G nor 4G

How Samsung Galaxys5 connent 3G or 4G

1 Now Go  to settings ->
2 network connections ->
3 more networks ->
4  mobile networks ->
5 network mode
6 changed it from CDMA to LTE/CDMA. Reboot it first

If not, you can attempt fiddling around in the accessible 3G or 4G networks and make sure your contributor information.
One more choice would be to make an effort toggling airplane mode to obtain it to connect.

If not anything appears to be functioning for you we woudl propose bringing your smasung galaxyS5 back to where you got it to notice if they can repair it. If they can not, they will probable give you a alternate mobile phone. superior to do that than forever be aggravated!
How Samsung Galaxys5 connent 3G or 4G

 
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