VPN eating hotspot data

Hi everybody. I know this subject has been posted before but just giving report of my experience thus far.

Using OnePlus 12R on Mint Mobile “unlimited” 40 Gb high speed/10 Gb hotspot plan.

My plan recently rolled into the new month, with a fresh 10 Gb of hotspot data. About a week in, I received a notification that I had used nearly all of my hotspot data. I thought that was odd. I’ve used my hotspot to connect an old iPhone before but didn’t think it was that recently. My phone settings are to turn off hotspot if not connected to within 10 minutes. I contacted Mint support about it and seeing as this was prepaid, they can’t really tell what’s going on. I told them that I’ll make certain that my hotspot remains off and if I still end up running through my hotspot I’ll let them know. I had a sneaking suspicion that my VPN usage was somehow contributing. Couple days later, I have a bunch of stuff to order, and end up firing up the VPN (Proton VPN for the record). Before long I get notification that my hotspot data is all used up. So I’m pretty certain that’s what’s going on… I’m unclear as to how a VPN tunnel would appear similar to another device tethered to my network connection though. Would that be the case for https traffic as well? DNScrypt? Curious to know also, if others have had better results with different VPN providers.

TLDR: Proton VPN on Mint Mobile will result in your untimely hotspot data cap.