Self assessment payment

In my self assessment return on the gov.uk website the calculated amount owed due to hicbc was around 1300. For some reason when I try to pay, the amount owed is shown as 0. Also When I go into the self assessment on the HMRC app the amount owed is 0. Any ideas?

Hi,

If it is more than 72 hours since you submitted the account and it still shows as 0, please contact our Self Assessent team.

Self Assessment: general enquiries

Thank you.