Overpaid Flexible ISA DURING tax year, but fine now

I put £15,000 into flexible ISA "X", and the accidentally also put £10,000 into a different flexible ISA "Y" during the tax year. In the same tax year I realised my mistake and have withdraw £5000 from ISA "x", so now only £20,000 was put in during the tax year. What should I do about the period of time during the year I had put more than £20k in? I fixed the situation already. Do I need to do anything?

Hi,
Any interest arising from the excess in the ISA, would be declared as untaxed interest, along with any other untaxed interest and declared on a self assessment tax return, if you are required to complete one, or in witing to HMRC, if you are not not.
Thank you.