Interest and disposals on Accounts in a foreign currency

I have a Wise account with money in GBP, USD and EUR. The accounts can earn interest. I believe the money is invested in a fund. I only have access to the total amount of interest in my pot now. There is no monthly breakdown, and I cannot access the specific value of the interest at the end of April last year. How can I report this in the Self Assessment form? (I could work out how much money I had and for how long and estimate the amount of interest assuming the current interest rates. Then if I check the figure on April 5th 2024, I can report the whole difference as my interest for 23-24. This may not be accurate to the penny, but would it be acceptable?) Disposals I asked for a report from Wise and they send me a report with information on disposals - total is Gain £0.14 and loss £0.28 Where do I report this. Is it possible to calculate from the figures relating to the disposals what my interest was for 22-23?

Hi

Only whole pounds should be declared in a self assessment tax return.  You can round up or down to your advantage.  
Any interest or gains of less than £1.00, should be rounded down to £0.00 and the appropriate box left blank.  The online tax return counts '0' as a number and generates an error message.  
Where this happens, delete the '0' from the box, to leave the box blank.  Losses are claimed in the Capital Gains section of the tax return.

Thank you