I've seen a few folks mention this in The Raiser's Edge Users Group Support Forum. You might try a quick reset of your session:
If the pop‑up appears again, click Remind me later. You can also try using an incognito/private window or switching to a different browser to rule out any browser‑specific issues.
If none of that resolves it, I’d suggest reaching out to Support so they can take a closer look.
The issue seems to be resolved. I have access to NXT again.
Yup! I'm working with support right now. Support is also having the issue on their end.