Yaalago watches your GDS sign-ins and tells you the moment a set of credentials stops working.
When a sign-in is rejected, Yaalago disables that credential in your account, stops retrying it, and emails your system admin so you know before a user does. If your agency has another active credential on file, the PNR request goes through on that one and work continues.
Once you have sorted things out on the GDS side, open your credential settings, enter the new password, and use Save and test. A successful test puts the credential straight back into service.