Redirection to advertising sites or ebooks

I see this (sent as a message on insta - I have not tried other types)

although the text itself does not make any sense because it leads back to the original URL

but I can assume that the security system on the hosting
in the meantime checked the REQ and after making sure that everything is ok, then made a redirect (allowed traffic)

and insta sees the redirect and protests

as for advertisements - I can assume this is the reason (although I don’t know exactly what you saw)