I have a survey which collects plant species data within repeats. I have 3 fields which sum data from the repeats to create a total count of items recorded in the repeats, and a summed total calculation. This is now only working intermittently - sometimes it works and sometimes it doesn't and I can't see anything obviously wrong.
I can send the XLSX form through privately?
Are your Sum fields outside the repeats? What exactly goes wrong?
May be some of your questions have a relevant expression? If so, if your question is not relevant its value will be nulled, and then the sum will give you a null value.
1+ null = null
To avoid this, you could use the conditional visibility expression in the body::esri:style column instead of in the relevant column.
I don't think this can be the issue as it doesn't explain why sometimes it works and sometimes it doesn't when entering exactly the same data into the form?