Errors on HMRC Online data - in Savings and Investment

I phoned HMRC to query this data which is showing on my 2024-2025 tax estimate. The amount displayed is clearly wrong and may have been for years if it is carried forward. I asked if HMRC can tell me how it originates ie which bank or banks may be submitting data as I have no knowledge of why this figure exists. The call handler said they could not tell me so I am unable to move forward in understanding where this data originates from. The only advice I got was to write in. I do not understand why they cannot advise me on the phone. The frustration at this response was multiplied given the excessive time it took (over 2hrs) to get through due to several cut offs automatically by their system. I suspect given we hear a lot about backlogs I am not gong to be able to get this simple request resolved. Anyone know why they couldn't tell me the source of the data over the phone? Thanks David

Hi wyattd,
We would be able to give some details of the bank/building society information over the phone.
You can contact HMRC here:
Income Tax: general enquiries
Thank you.