Bent engagement ring with diamond falling out!!!

To
My fiancé just proposed last friday with a beautiful rose gold diamond ring (that was in the thousands mark) and tonight i took it off my finger to see it was deformed and the diamond is wobbly. I have NOT hit it off anything and have not had it near water. Its been on my finger a matter of days so as normal i was trying so bad to keep it safe. Its such bad quality. Its insured but I want my fiancé to get a refund as this particular store has 1* reviews for easily broken jewellery and horrific customer service. Apparently they dont do refunds, but leave that part out when you purchase the ring. We plan to go to the shop tomorrow. What do i do here guys im livid!!! I love my ring but it has to go😞