Very upset

I've been treated with ketamine infusions before and I wanted to get a booster infusion this week. Depressive symptoms have been creeping up again. Found a doctor and got in all my paper work and just now he tells me that he's not going to do it unless I can do at least 3 IV sessions because it won't help me if I just do 1. I've done 1 in the past and I've found it to help. Is this normal? Very upset.