Add APN to Visible Midnight


I have two Visible Midnight phones that are unlocked and am trying to use TextNow sims on t-mobile). The default APNs for T-mobile are not working and one of them needs a few changes or a new one added in. I do not see a way to add a new APN … no new option under the hamburger menu (only reset to default). When I modify the one and save it, it soapears entirely. Only way to get it back is reset to default without the needed changes. Is there a way to add APNs to this phone?