I can't log into my Apple ID account on websites / can't download apps / edit Apple ID settings I changed my sim to another sim because I was on vacation in another country and my "trust number" in the apple id settings was changed to the new temporary sim number. 

And now when I came back and I want to change it back to my real sim number (in my country - I already replaced the sim) I can't remove / add / edit 
it to my real number it says all the time some "error" like could not connect to iCloud / Could not verify phone number and below it "We cannot process your request, please try again later." 

For some reason I have two factor authentication and when I try to log into my Apple ID it says below the login form in yellow box - "We cannot process your request, please try again later." I get 6 digits code to my phone but I have no where to enter the code... Nothing is showing up.. 

When i try to download apps it says that "App store and apple music cannot process your request at this time" Please I need help I don't know what to do anymore!
Best thing to do in this case is find a working web browser and try signing into iCloud.com or appleid.apple.com to be sure your account isn't locked or you have a password issue.

When that's sorted, go back to the device and try one thing before you move on to the next. Check date/time on the device since most Apple log in are very strictly SSL / HTTPS checked and time being off will block the log in attempt as does network shenanigans like man in the middle type privacy attacks (or "snooping by someone" using http proxy).