Contributed to 2 Flexible Cash ISA in tax year 2023/24

Hi team, I contributed to my existing Cash ISA back in April 2023. A few day aga I mistakenly opened a second Flexible Cash ISA account with another provider and transferred £1,300 into it. I realized this is not allowed so I withdrew £1,300 from the second Flexible Cash ISA account. No interest has been paid yet. 1) Do I need to report this error to HMRC and how? 2) What should I do with the second Flexible Cash ISA account? Should I notify the provider for my error and ask them to close my account. 3) For the £1,300 quota, can I still use it to contribute into my other LISA / S&S ISA?

Hi KY Wong,
1. As you have already withdrawn the funds and no interest has been paid, no.
2. You need to determine which account you wish to keep open.
3. Only if you have not met the £29k maximum for the year
Thank you. 

Hi team, thanks for the reply When I try to close my Cash ISA with the second ISA provider, as I have deposited the fund for 3 days, I have accrued an interst of £0.48. They can't claw it back due to operational issue. What should I do with this interest (as I should NOT be entitlied to it)? Do I need to keep any record or report that? Thanks.

Hi KY Wong,
As this interest is taxable, you would need to add it to any other taxable interest you receive and declare it either through your tax return or through PAYE.
Thank you.