Bupe works well sublingually or snorted. It's barely absorbed orally, something like 10% bioavailability.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2994593/
Swallowing it won't work well/at all (so doing that was a waste), but you can dose it under your tongue or snort it. Don't use it if you're dependent/addicted to another opioid. It'll give you precipitated withdrawal (bad shit).
https://psychonautwiki.org/wiki/Buprenorphine
It's seriously potent. Start with like 0.8mg (sublingual) or 0.6mg (snorted) without opioid tolerance or it'll make you nauseous as fuck.