pronoun reference ambiguity
A pronoun that could point to more than one noun.
A pronoun must point to one clear noun. He, she, it, they, and this all fail when two nouns could take them. Rita told Dana she had missed the deadline does not tell who missed it. Repeat the name, quote the speaker, or recast.
Examples
Use Rita told Dana, “I missed the deadline.”
Avoid Rita told Dana she had missed the deadline.
Use The hall and the lock failed inspection. The lock was fixed.
Avoid The hall and the lock failed inspection. It was fixed.