Black spot on a cattleya

[Jo Ann]

again… it never attacks any of the other orchids just the cattleya’s …it happens so fast …I thought over potting what was causing it…so this time I left the plant in its a 2 x2 in pot that was from the nursery it came in thinking that was probably the safest thing to do until I could pot it up right … how can a plant rot in a 2 x2 inch pot…?.. Please help what can I do to stop this other then give up on cattleya’s? I know there has to be a solution…