Thanks for reaching out to us, sarah-cain-adfin.
I've checked your post and found out that you've posted similar questions twice. The duplicate one was already answered by my colleague, Rubielyn_J.
You can use this link to view her answer where she shared some steps on you can successfully submit your return: https://quickbooks.intuit.com/learn-support/en-uk/other-questions/re-does-anyone-have-any-suggestion....
I'm also adding these articles to learn how to track the payments you make to HMRC once you submit a CIS return in QBO:
Please let me know in the comment section below if you have other questions or concerns. I'll be around to assist you.
