Pot. Makaha Enchantress Wine Bright yellow and black leaves and pseudobulbs

[Psych Chick]

Hello everyone,

I find myself in need of a bit of help concerning my cattleya (Pot. Makaha Enchantress 'Wine Bright'). I repotted it a few weeks ago using Pro Mix for orchid (only thing I could find- before it was Fafard's orchid potting mix). About a week or two ago it started losing leaves and turning brown-black and yellow, both the leaves and the pseudobulbs. I researched it online but can't figure out what is going on exactly , so I was hoping for some more expert eyes to help me out on the cause so I can apply the proper treatment and hopefully save it.

Thank you!