I think my phal is trying to commit suicide

[mayres]

With as big of bark as it looks like from the pic (is it all that size down to the bottom?) your plant could be suffering from dehydration (not enough water). Unless your humidity is very high the roots may not be able to get enough water to properly sustain your plant in that media - especially if it is a quality of bark that is not absorbing and retaining water well. Depending upon your conditions you might consider a media that is less porous. Sometimes when repotting into bark like this you need to actually soak the media and roots for a good period of time until the bark gets in a water retaining mode - maybe a good 20-30 minutes or more each time you water for a few months.