Riman2024!

I have received £1,974 in dividends from a number of overseas companies. I have entered these figures, by company and country, along with the amount of foreign tax paid in my tax return along with the percentage relief (mainly 15%) I am seeking. Yet I go further with the form I am told it is not possible to calculate the amount of relief I am due. It does give me an optional box to specify the amount I am claiming but I do not know how to work this out - is it 15% 0f £1,974? I have entered all the information asked of me. How am I expected to proceed?