APN for Galaxy Grand Prime

[Drachenomics]

Hi, Im trying to get my mom's new phone on the consumer cellular network, and im running into a snag on the apn inputs. Ive tried every apn settings list I could find, and cannot get messaging to work. The phone is a Galaxy Grand Prime, formerly on MetroPCS network. As a side problem, most apn settings want a value of 410 for MNC, but mine is stuck at 260 and entering anything else make the new apn disappear. Any help would be greatly appreciated. Thanks.