Coinos lists these contact routes (checked just now on their mint's info endpoint, mint.coinos.io/v1/info):
- Nostr: npub1w27mc4aa6m0ufe3xs5z3m6qyr52gc0rglept7vqlwx4xeaf72tasnqz70r (a DM or a tagged note here may get seen faster than email)
- Email: support@coinos.io
- X: @coinoswallet
There's also a public Telegram group, Coinos Bitcoin Wallet Chat (~980 members): https://t.me/coinoswallet
For the bug itself (inbound works, outbound fails, can't log in), the server code is open source and has a public issue tracker. Others have filed login and payment bugs there: https://github.com/coinos/coinos-server/issues
Tip: don't post your password, auth token or seed anywhere while asking for help. Just your username and what you see.