Sunken leaf spots on masdie

[harpspiel]

What is this? Bacterial brown spot, something fungal? Just wondering if I need to do or buy something special to treat it.

Day 1:


Day 2, back of leaf:


Day 2, front:


This Masdevallia ignea ‘Valentine’ x discoidea ‘Anne’ keeps losing leaves, it’s down to 2 (but has at least 4 new ones developing). It gets these sunken patches, they start on the back, spread to the front and then turn brown. I thought it might be crowding or water sitting on the leaves, so now it’s in a spot where it doesn’t touch anything and water evaporates quickly, but I just lost another leaf. I cut them off with sterile scissors (maybe not sterile enough? I hold them over flame, but I could buy single-use blades), and when I moved it I sprayed the leaves down with Hydrogen peroxide - maybe that just ended up spreading it?

My temps hit 80 but have a good daily drop into the upper 60s, but the seller was not growing it cool. It should get warmth tolerance from the discoidea and it doesn’t have any of the black speckling that you often see indicating heat stress in Masdies. It was very healthy and in bloom when it arrived, great root system. I checked the roots but they were so healthy that I didn’t repot, just left it in the bark mix it came in.