Phal in distress - please Help!

[DeniseKoh]

Hi All!

I recently bought a pot of phals abt 2 months ago.. they had quite a few buds and were blooming pretty well. I tried not to water the plant too frequently abt 3-4days once. However, I noticed the roots have started to shrivel up, but I don't want to over water the plant. Some buds are growing but most of them shrivel and drop even before they can bloom.

I live in Dubai, it's practically a desert, so my air conditioning is on most of the time and i've set it to 20deg. The air tends to be a little dry so i don't think there's much moisture. Should i re-pot the plant? I'm pretty sure i'm killing it!

Also, after the flowers have bloomed, should i cut the stem? Where should i cut it? I'm concerned if the stem grows too long then the plant might have trouble being kept upright. Sorry if I seem to be asking silly questions!

Pls help! This is my first plant I've tried to post the photos.. Thank you so much!!!