I spent three days solving this problem and tested the following tips which worked
1- Building the trust of game installation paths by antivirus by (Add or remove exclusions)
2-add msfs in Allowed app firewall in windows
3- Test disabling the antivirus
4- Give admin access to the kernelbase.dll file (tutorial is on YouTube)*
5- Disable xmp in bios, but first watch the tutorial on YouTube
6- Don't rush and act calmly to think better :)
7- There is no need to reinstall or fresh, first you should consider all the possibilities
8- Remove and install game service and xbox service in Windows through PowerShell (YouTube)
9- Important point** The Microsoft account that you log in to the game must be logged in to the Xbox Windows program...exactly the same account....I even logged in the same account in Windows itself...it worked for me
10- Be sure to do the ninth item carefully
11- Try to temporarily delete miscellaneous mods from the community folder
12- Remove the graphics driver with the ddu program in safe mode and install the updated driver
13- If you have already downloaded the packages and encountered this problem during the update, you can temporarily rename the packages folder and delete the game and reinstall it.... Note that we delete the game, not the packages that It is in the path of appdata
14- You can delete all the files in the path below, except for the packages folder, because they will be created again when the game is run.
C:\Users\username\AppData\Roaming\Microsoft Flight Simulator
15- In the settings of the Windows region, select United State
16 - In the language settings of the system, download the text and audio packages of the English language (YouTube).
17-Use vpn or dns to log in if there is a problem
18- Be sure to run Steam program and msfs game with run as admin mode
19 I hope you are successful and if you solve the problem, teach others the tips (be kind)