Troubles with RSS on wordpress

Site URL?

https://utern.org/wp/?feed=rss2

I not sure whether it was because of plugins i added, but i do not think that is the case.
the rss doesn’t work in google chrome nor mozilla firefox, i wonder what is wrong.

the link to the error message on chrome is https://utern.org/wp/?feed=rss2
the firefox error message is like this… (below)

XML Parsing Error: junk after document element
Location: https://utern.org/?feed=rss2
Line Number 2, Column 1129:

i don’t know what to do anymore

Reset your feed options and check again.
There are some unclosed tags shown by markup validation that can also cause the problem.

https://codex.www.ads-software.com/Validating_a_Website

how would i reset my feed options?
I tried refreshing the page by ctrl +f5, but it didn’t seem to work. I tried validating my feed and it shows this (on the site). I am not quite sure what it means

https://feedvalidator.org/check.cgi?url=http%3A%2F%2Futern.org

Try this: Go to Dashboard >> Reading. There you will find feed settings. Reset to something other than what you have now and see if it helps.

I tried change the feed setting to different ones from the ones I have before, and the rss feed for comments and entries are still showing the same message.

Could plugins affect the RSS feeds? Not sure if it is the any plugins (or which one) that caused this problem.

I also tried deactivating all my plugins and changing the themes.