Someone help me with this phal? Black roots and floppy leaves

[2ysub2ysur]

I repotted this guy back in September and it definitely seems worse off now, even though it wasn't in great shape then. Hoping someone can diagnose it by looking at the photo.

At first I thought I wasn't watering enough (generally once a week, but I used the larger bark so it doesn't hold much moisture in), but watering a couple times per week didn't change anything.

Thanks in advance!