R6330 firmware 1.1.0.84_1.0.1 breaks login from Android Nighthawk app

[DickScheel]

I have an R6330 / AC1600 router. It has been working well for me for more than a year. A new problem started today. The WiFi connections are still working fine, but I can no longer log in to the router's admin functions with my Nighthawk app on my Android phone.

I have been using the app on my phone for a long time without any problem. Today I used the app to check for firmware updates for the router. The app connected to the router OK at first. When I checked for firmware updates, I saw that there was one available. I told it to go ahead and install the updated firmware. After it installed and the router rebooted, I tried to log back in to the router in the Nighthawk app. The app said that the login had timed out. I tried the login again, and again it said that it timed out.

The error message in the app suggested rebooting the router. I did that, and the login still timed out every time I tried it. I have also tried:

1. Exit the Nighthawk app and restart it - still fails the same way
2. Power cycle the phone, then start the app & try to log in - still fails the same way
3. Connect to the router via Chrome web browser on my laptop (via WiFi) - I am able to log in as admin
4. Uninstall the Nighthawk app from my phone, then re-install it and set it up again, then try to log in to the router - still fails the same way

My phone is a Samsung Galaxy S10, running Android 11 (patch level August 1, 2021)

The Nighthawk app is version V2.11.0.1661

The router firmware that I newly updated to today is version V1.1.0.84_1.0.1

[michaelkenward]

Are you sure it isn't the Nighthawk app that is the problem?

A recent app update has caused widespread grief on some Android devices.

[DickScheel]

I can see that the problem could be caused by either end of the connection - the Nighthawk Android app, or the router firmware. I don't access the app very often, so the problem could have started earlier than when I first observed it on September 1. I typically use the app once a month to check for router updates. The app started up and connected to the router OK on Sept 1, but that didn't require me to enter login credentials (I assume that it used a stored token of some sort, from the last time I needed to perform a login). It was only after the firmware update was installed & the router rebooted that the login dialog was presented, which then failed.