Worst service ever, incompetent, £ inaccessible lost my data

Set up a Post Office 2 year Online Bond 5 account four years ago. Linked to my current account, fair idea for security, so anyone who steals my login can only transfer money to my current account. BUT when I tried to transfer out last week my bank details were not showing as an account to transfer my money to. This is the account where the money came from in the first place, and I have WRITTEN CONFIRMATION of those details from the Post office. I phone Customer Services at my expense, they claim no account linked! Arrogantly refused to help over phone because of DATA SECURITY. These are the clowns who lost my data!. I had to add it again as a transfer out option. Then I tried to transfer it out again. Guess what because I had added a 'new accoount' my money will be frozen for a minimum of 5 working days (Monday does not count) When I try to login it first said password incorrect. NO, I do not forget my password, your computer suystems are incorrect. A week later error message changes to invalid userid. Again I have in writing the userid I use, it is the one provided to me by the Post office.

So I still have no access to my money..I see a call to a banking complaints service or ombudsman coming.

Product: Online 2yr bond 5