Bot hosted on heroku make some command doesn't work

Question

So, I hosted my bot on heroku, and try to apply it to be publicly posted, but when I see the review it said my majority of command doesn't work and it's weird because if I run the bot itself on my pc, everything seems fine, but on heroku the logs will say "changed status from up to crashed" or something, is there a way to fix it, or I should use vps to host it, but if using vps is there any tutorial how to host it ?

Cheers.