Problem with generating user token

[r129-parts.eu]

Hello everyone! 
I have some weird and annoying problems with generating User Token for production with my real eBay account. 

If I am using Auth'n'Auth, then I got  automatically redirected to link - https://signin.ebay.com/logout/confirm
I tried to clean the cache, change browsers, and even computers. Nothing changed.
If I am using OAuth method, then it redirects to eBay login page and asks me to log in. After succesful login 
Then it redirects to my website where it reads ?code= / User Token . 
This user token doesn't work at all. Tried in API Explorer and in 2 different SDKs. Errors -
2023-07-06T06:20:23.960ZFailureAuth token is hard expired.Auth token is hard expired, User needs to generate a new token for this application.932ErrorRequestError1271E1271_CORE_APISELLING_19187371_R1

Also after successfully login in eBay in my developer account  in the User token section doesn't show this User Token what I received in my website. 
If I am trying again to press the button with choosen  OAuth, then it doesn't redirect at all but gives this error in the link
https://developer.ebay.com/my/auth/?env=production&index=0&auth_type=oauth&errorId=14000

I don't have any idea what I am doing wrong and what else I should try. 
All I want is to create a user token for my real eBay account so that I can read data about my listings on my website. 

Thank you!
Juris. 

[r129-parts.eu]

After posting this post for about 2 hours randomly everything started working fine. No idea what happened. 🙃

[developer_support@ebay]

Hi @r129-parts.eu 

Error "Expired IAF token"  indicates that the eBay IAF (Identity Assertion Framework) token that you used, has expired and you need to use the new access token. 

OAuth user access token remains valid for 7,200 seconds (2 hours) from the time it was generated. After the token expires, you will need to renew it using the supplied refresh token.

For more details please see "The authorization code grant flow" and "Using OAuth with the eBay traditional APIs"