Kindly find below steps on how to remove proxy address for various devices, however caution should be taken in ensuring the APN ID is maintained.

N.B: please note this does not eliminate the need to carry out the required troubleshooting before proffering this resolution.

HTC One

Click Settings

Mobile Data

Network

Access Point Name

Select MTN GPRS

Tap Proxy and Delete the number in the field

Tap Port and delete the number in the field

Save

Samsung Devices

Click Settings

More network

Mobile Network

Access Point Names

MTN WEB/GPRS

Tap Proxy and Delete the number in the field

Tap Port and delete the number in the field

SAVE

Windows Device

Settings

Mobile +SIM

SIM Settings

Turn ON Manual Internet APN

Delete PROXY and PORT

Save

INFINIX and other Android devices

Settings

Click More

Cellular Network

Access Point Names

MTN NG (WEB/GPRS)

Tap Proxy and Delete the number in the field

Tap Port and delete the number in the field

SAVE

Blackberry 10 devices

Settings

Network and Connections

Mobile Network

APN

Click Reset Defaults

Click restore