Vet Refusing Lantus

Hi All,

My cat was diabetic about 1.5 years ago, went on Lantus and went into remission after sometime. It seems (after bloodwork) he is again diabetic. Our vet is now refusing to prescribe Lantus now that Senvelgo or Prozinc is now available. Only one of those is an option due to him having keytones previously. I find it suspicious that this vet says they won't prescribe it now but I can pay for Senvelgo at well over 250 a month.

I placed a call to the vet to ask if this is a personal refusal or a legal issue but I haven't heard back yet. I'm in the U.S., this just seems odd and I feel like we're getting hosed on costs with this place.

Edit: I don't know why Senvelgo was given an option as the doctor openly admitted it was an issue with prior keytones in his urine. Prosinc, to my understanding, is the only option offered.

Final edit: My old vet about 40 mins away who was great when I lived closer, will prescribe his Lantus. I'd rather drive and get better care while paying less vs deal with this place. Thanks for all who replied.