HELP Please I need help

The group rally protects the Lake Tahoe , Believe that only
low-impact recreational activities should be allowed.
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I think thats correct sorry If its not im not the best
at this
Answer:
Original: The group rallying to protect Lake Tahoe believe that only low impact recreational activities should be allowed.
Revised: The group rallying to protect Lake Tahoe believes that only low-impact recreational activities should be allowed.
Explanation:
According to Grammarly, it states: "It seems that the verb believe does not agree with the subject. Consider changing the verb form."
I hope this helps you in any shape or form.