Relocation Repayment ?

I was at Amazon for 5 years and I transferred teams in October ‘24. I was requested to move to SF and given a $7K relocation.

I quit 6 months later and now got an email saying I owe them $15K since I have to pay the “pre-tax” benefit vs the post tax which is what I received. This is literally insane. Has anyone had any success with either not paying or getting It waived?