Invisalign tray not grabbing one of the attachments since early in treatment. Is this going to cause problems later on?

Decided to go with dentist for treatment because he was $1000 cheaper than the orthodontist which is something I am now regretting. I'm on tray 7/10 in the first round and my dentist doesn't seem to know what he's doing. I have had a problem with one of my attachments not grabbing the trays since early in the treatment. When mentioned to doc, he said "your tooth will shift into the tray, that's how they work." I have 15 attachments and this is the only one with a problem. What do I do now?