Pre approved for a mortgage then advised the loan cannot proceed

I was pre approved for a mortgage loan, found a house, made an offer which was accepted, I sent the contract to USAA who proceeded to have a underwriter finish the process. The underwriter advised that because I had open disputes on my credit report, they could not proceed with the loan.

Now this is the same credit report that was used to pre approve me and I think that if this was grounds for not being able to proceed with the mortgage, I should have been either denied for pre approval or advised of the situation during the pre approval process.

The worst part of it is that there are no longer any open disputes as the last dispute was finalized 18 days ago.

Now I have wasted a lot of time and money due to my trust in USAA. Ive never had any issues with USAA in the past but this issue is cuasing both myself and my entire family to do our financials elsewhere. Between my siblings and parents we have numerous accounts with USAA.

I would also like to add that I am putting 20% down on the house and was advised by a USAA representative that because of this I would have no issues securing a mortgage.

Sincerely,
Kevin Parsells