Disappearing balance when using Post Office ISA holding account

OnionPeeler

Yesterday I applied for the "big name" Post Office ISA (4.4%) that I saw on MSE. I was surprised to discover that it uses a holding account and the whole product seems to be operated by a third party called One Family. As a precaution, I only paid in the minimum £100 deposit with my debit card. The holding account has a low interest rate of 1.25%, so I wanted to get my money into the ISA itself and then repeat the process once the ISA deposit was showing on my web page. After some exploration I found an option to transfer to the ISA, so I tried to transfer the £100, but I got a pop-up message saying that I couldn't empty the holding account. So I went back to the holding account intending to pay more in, but I was shocked to see that the balance has reduced to zero. So I don't know where that money has gone. On the ISA Overview web page it shows "The total value of your ISA is £0", "Your remaining ISA allowance for this tax-year is £19000" and my Holding Account Balance is £0. So the information doesn't add up and I've sent a secure message to complain about it (there is no telephone number to contact). Based upon my experience to date I would not recommend this product.

OnionPeeler

I've now discovered that the Post Office ISA website takes a few days to update, but my payment did finally appear in the holding account. When I tried to open the ISA originally, I accepted an option to create a holding account, but now I realise that I probably shouldn't have because it complicates matters. I had to subsequently navigate the website to specifically open the Easy Access ISA and then transfer from the holding account to the ISA. The website only allowed one transfer, so it appears that the Easy Access ISA is treated like a fixed rate product, where it is locked after the initial deposit. I still haven't received a reply to the secure message that I sent, so I won't be investing anymore money with them.