Thanks for contacting TextNow. I have taken a look at your account and see that there appears to be an issue with the device you're using that is causing login issues. You can take a look at our support article here: https://supportfree.textnow.com/hc/en-us/articles/360021902532
for more details, but essentially it looks like your phone is not set up to work optimally with our service, this could be for various reasons.
Typically if the phone has any sort of customized operating system or if you're using a device emulator or anything like that, you will no longer be able to use your TextNow account on that device. It is also possible that you're simply using an outdated OS or TextNow version, so if you have updates available for those please update and try again.
Please let us know if you have any questions or concerns about this.