I'm aware that this issue has been mentioned before, but none of those solutions have worked for me and it feels somewhat more aggressive than the issue stated before.
The majority of the time I open an adobe app on my machine, it asks me to sign in. Especially after restarting the machine, but sometimes I might have to restart an app and it will ask me to sign again and sometimes it will close an app whilst I'm working on something (fortunately, it usually asks if I want to save first) and then ask me to sign in again when I re-open it. Which is very annoying.
What's worse is, sometimes it just gets stuck in a loop. I'll sign in, it will accept it and open the app and then the app will imediately close and it will keep doing that until I restart the machine. Although sometimes it might do it two or three times and then work fine.
It even seems to happen between apps, I might have Premiere Pro working fine and then open After Effects and get this behaviour, whilst Premiere is logged in and working ok.
So far, I've reinstalled Windows (Windows 10 Pro 20H2 on build 19042.928), reinstalled Creative Cloud (currently it's version 18.104.22.1684 and I'm using the latest 2021 builds but I've been having problems with this for a long time, it just seems to be getting worse and more frequent.)
I've also tried numerous times restarting credential manger, but this doesn't seem to help either.
The machine specs are: Ryzen 7 3700x, 32gb of 3200mhz ram in dual channel and a GTX-1080.
Windows and Creative Cloud are both installed on the same 1tb Sabrent nVME SSD (but I do have a second drive with some other programs installed, then a third drive which has the documents/music/pictures libraries and fourth drive with the videos libraries on and then additional external hard drives and SSDs that I hot swap where most of my actual projects and video files are stored.)
there's something on your computer (eg, av, antimalware, cleaner, defragger etc) that's interfering with your sign-in credentials.
with the frequency of the problems you're describing, your av program and a possible malware sniffer are the more likely culprits. which av program do you have and which, if any, antimalware prog do you have?
I used Avira and Windows Defender
there have been reports of avira causing problems, Solved: Avira Antivirus detects spy software inside Adobe ... - Adobe Support Community - 9701206
i don't know if that's causing your current problem but i would test, if i were you.
I completely uninstalled Avira to test it, and still experiencing the problem.
Reach out to technical support. Maybe they can identify the conflict.
1. With a browser that accepts cookies and does not have script blockers, please log-in to your account portal below.
2. Scroll down to Contact Adobe or Adobe Help Center.
3. Online chat is available in English 24/7. See screenshot.
4. In the chat box, type AGENT followed by enter key and wait for a human.
5. Alternately, phone customer service M-F during normal business hours.
Please keep us posted on what happens.
Sorry for your frustration with this.
Generally the solutions here will help with that issue.
If the solutions there don't help, the solutions here are typically the next steps deeper in causes
Based off of your description it sounds like you've done some of these (maybe all?).
Like others mentioned, it's good to rule out third party software which might be interfering and you can also contact support for assistance too.
Hope you're able to get it sorted soon,