Here is a solution to fix this error on your telegram account!
How To Resolve “Sorry This Group Is Not Accessible” On Telegram?
Telegram has many open and close groups which anybody can join to get all the latest updates about various things. You can join these groups by searching for them or by clicking on the link provided by your friends or family members. If you are a part of any group and you suddenly receive a “Sorry This Group Is Not Accessible” message on your screen then it is because you may be banned by the admin or the participants in the group.
This message appears when someone usually removes you from a Telegram group and you are put in the removed user’s list for that group.
Here are multiple ways to fix it and join the group again.
1) Restart your mobile phone and try opening Telegram again.
2) Go to the Google Play Store or Apple App Store and check whether your app is up to date. If not then update it right away.
3) Clear all the cache from settings and try to access the group again. Settings > Applications > App Manager> All apps > Telegram > Clear Cache
5) Make sure you have set your phone on the correct date and time and the correct time zone. If not check for date and time settings on your mobile. Settings > date and time > automatics date and time > automatic time zone > turn both the options ON.
6) Uninstall Telegram on your device and install it again. Log in using your same user ID again and check if the “Sorry This Group Is Not Accessible” error remains.
7) If any of the above solutions did not work then try and send a request to the admin of the group to remove you from the removed user’s list and add you again to the group.
8) The last option for you to fix this issue is to create a new account and join the group you want to form the new login id.