Its mean banking credentials entered into QBO is not working , either try to login into first into Online Banking account with the same details and than remove old information and Add banking details again . Also you might receive 301 error code which mean QuickBooks stopped all process and you have to enter your login information again
Check for Small and Capital , remove spaces in password and if you are using special character like %$#&* in your password , Take precautions while entering or Contact QuickBooks Support by dialing toll free Number +1-800-301-4813
CALL ☎ +1-800-301-4813 QuickBooks Technical Support
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