Potential ISA over subscription - advice please

Hello! I have held a Flexible Cash ISA with Bank A for some years now. In Sept/October this year (2024), I opened a second Flexible Cash ISA with Bank B. Since April 2024, I have paid ~£12000 into the Bank A Cash ISA and the cumulative amount (so including from previous years)was standing at ~£25000. In October, I deposited £1225 into the new Bank B Cash ISA In November, I withdrew £20000 from the Bank A Cash ISA to a current account with Bank C. Still in November, I then decided to move £15000 from that current account to the Bank B Cash ISA. The Bank A Cash ISA is paid interest annually - none of the £12000 paid in this year has earned any interest yet. The Bank B Cash ISA is paid interest daily - so some interest has been paid. I thought all that I had done was okay because - so far - my total money saved is (and will be) less than £20000 by April 2025 and because the money in Bank A Cash ISA is yet to earn any interest for me. I have since read that the money I withdrew from the Bank A Cash ISA, to my Bank B current account, cannot be then moved to the second Bank B Cash ISA without - for want of a better phrase - counting double to my £20000 allowance for 2024/25. I have queried this with the Bank B Cash ISA provider and they advised to contact HMRC. So I have two questions: 1. Have I inadvertently exceeded my ISA allowance? 2. What actions do I need to take either to rectify this or pay any tax owed? Thank you! Ben

Hi,
By withdrawing the funds and then depsoiting them in another ISA this is seen as new money and forms part of the 20k limit. Ymjcvou have therefore exceed this limit as you have deposited 12k, 15k and £1225. As  you have oversubscribed in the current tax year, you can contact your ISA provider to instruct them to remove overpayment amounts to correct the error.
Thank you.