Answer:
It is an error made when a writer changes the person of the pronoun.
It is an error made when the pronoun doesn't match the antecedent's number
Explanation:
A pronoun shift happens when a speaker makes a sudden change or shift from the third-person pronoun to the second-person pronoun which ends up confusing readers who do not know who the speaker is referring to.
This pronoun shift error is also made when the pronoun does not match with the number of the antecedent.
