My payroll tax has been rejected, I am registered and activated with HMRC but each time I try to submit it is rejected

Hello acsnortheast,

When the FPS gets rejected from the HMRC, it means that the credentials or ID and password are entered incorrectly. Let's go to the Government Gateway again and re-enter your credentials. 

Please refer to  the To enter your HMRC credentials section in this article to see the steps: Turn on RTI reporting to HMRC in QuickBooks Online Payroll.

Once done, refile the FPS. 

Let us know if you have any questions.