Fix: Delete StreamerKit configuration files
1. Win+R (to bring up run dialog), enter %localappdata%\LIV\StreamerKit , and click OK
2. You should have a list of json files, could you just archive all of them (Send to -> Compressed (zipped) Folder)
3. Delete all file except the zip file just created
4. Re-authenticate Twitch, double check you are authenticating to your account, see if chat/etc is working.
5. Re-authenticate with Streamlabs/Streamelements and test donations or merch alerts from their service