how do I remove this from RSS feed

I use the WP RSS feed to email blog posts summary to my mailing list.
But the RSS feed is adding this block of text to the end of every post excerpt and I cannot see how to get rid of it.
Can anyone enlighten me.?

https://nimb.ws/pR7WU8

• This topic was modified 1 month, 4 weeks ago by Jan Dembowski. Reason: Moved to Fixing WordPress, this is not an Everything else WordPress topic