Comment marked as spam.

Hi I got problem with commeting as title says.
When I try to comment with my bot using 25 accounts with 25 proxies (1proxy per acc) it is automatically marked as spam, no matter if I try to hide link (ex. c0m (dot)com) etc., but even if comment is like "Great video, thanks for upload". I tried to comment manually from my browser using private proxy or my personal IP and same things happens. When I setup my bot it grabs like 500 videos to comment, says that like 450 are commented but maybe 10comments displays correctly (not marked as spam). Ofc I setup delays between sending comments...
Youtube is clever and when I comment from an account comment displays correctly but when I change proxy and login from another acc it is marked as spam.
Does anybody know how to do a mass youtube commenting correctly?

There are many factors involved in yt spam detection, but your first line of defense are trusted ip's/proxies and quality yt accounts.

Another thing to make sure is, for both your computer and your bot, user-agents (browser fingerprint) must be randomized when doing comment posting/rating. And the usual cookies/flash cookies cleared between sessions.

too many comments too fast, all get marked as spam. that was from just
one experience of my own.

Its best to slow it down to around 1-2 minutes per comments. test test test.

Your 25 accounts are marked as spammers by the YT system, leave them for 2 weeks and they will be unbanned. For now you will need to use different accounts and different proxies.