Likely causes
- Wrong account type: social login versus email account
- Password changed on the vendor side
- Region mismatch between vendor and assistant accounts
- Vendor service outage
- Too many failed attempts triggering a temporary lock
Quick checks
- Log in to the vendor app with the same credentials
- Check whether the account uses single sign-on
- Confirm the vendor region setting
- Check the vendor status page
Step-by-step fix
Reset the vendor password and log in to the vendor app
Remove the skill or integration from the assistant
Re-add the skill and link again
Use the provider login if single sign-on applies
Wait out a temporary lock, then retry