Emails with a link to Airtribune will not be sent

Hello
Make sure every email I send comes with a link to Airtribune. Ex.

[https://airtribune.com/apia-2019open-valle-del-risaralda-2da-valida-camp/pilots](https://airtribune.com/apia-2019open-valle-del-risaralda-2da-valida- camp/pilots)
Without information/or errors it simply won’t be sent (even though they are stored in the sent folder)

This can be done from another email address without any problems.
What can I do?

Maybe it’s just because the emails are being prevented from arriving and are not displayed in SPAM.
Because if I send it from a different email address, it won’t appear in the inbox.
In any case, it is stored everywhere in (Sent), but it never appears in the Bluewin inbox and nowhere else.

In the meantime, the emails with this link end up in Bluewin’s SPAM when I send them from my other account. And then even if I use the rule that is provided so that emails from this address should not be treated as SPAM.
I strongly suspect that Airtribune’s website has been blacklisted.