Change in Purchase invoice payment?

The way a New Purchase Invoice is paid appears to have changed. It used to be that I entered a New PI and then go to pay the invoice from either bank account ,or via customer etc.
Now (version 15.1.40 latest), I enter in the same way, allocate customer and expenses account and create the invoice, but it now shows as PAID IN FULL although I havn’t made a payment, neither can I see it being deducted from a bank account.
Super program, and sorry to be a pain (if its me doing something stupid - I did read the latest guide for Purch invs, but it doesn’t seem to cover my problem)

I see I now have a Supplier Credit Account which I don’t recall having before and all the recent supplier invoices which I have paid has bben transferred to that account and is paying new invoices from it. Manager seems to have automatically paid the suppliers (from where I don’t know, and credited (my) payments to Suppliers Credit.
I am confused.

Did you first enable the Suppliers tab, then create suppliers, before creating purchase invoices? If there is no properly created supplier designated, Manager doesn’t know where to put the transaction.

Yes I have created suppliers and the purchase invoices have a supplier allocated to them.I just upgraded to the latest version, and on looking at the Suppliers (credit column) Manager has reallocated payments to suppliers credit for some invoices over the last 9 months or so, but not all of them. Why would it do this? I have used Manager for going on 2 years and this problem with purchase invoices has not occurred before (I have approx 200 purchase invoices in the system)
I tried to do a restore from a backup but it comes up with an error too, hoping it would
miraculously correct things.
Still confused.

OK, problem solved. I had put through an invoice but omitted the VAT, but paid the ful l amount from my bank account.
Manager had credited Supplier Account with the overpayment and paid subsequent invoices from it,although I paid them from the bank account.
I did an edit to add the VAT to the invoice and that cleared the Supplier Credit, so now I might be able to claim the VAT back too.
Sorry for the trouble which was my fault.

I had the same problem.
For some reason on some purchase invoices the vat wasn’t included in the transaction.
All I did was created a different expense account in my chart of accounts (as my accountant advised me to) and edited/allocated those items to that account.
This ended in what I drilled down to find was an overpayment to suppliers, I found the offending invoices and the vat wasn’t added and I can definitely say that I did include the vat at the time of the transaction so I presume this to be a bug?
It wasn’t too difficult to rectify but still caused a little head scratching and think @lubos should still be made aware.