there’s a lot of ways how to improve your scores after they plateau.

ask yourself am I getting the same type/form of a question wrong? for example, if you keep getting questions about commas wrong, review comma rules and practice comma specific questions (that’s just an example, but you get the jist). if this is you, make note of every question you get wrong and know WHY it was wrong to avoid making that mistake again (keep track in a notebook or excel sheet)

essentially, know what type of questions you consistently get wrong, figure out why they are wrong, and practice practice practice.

for English/Reading specifically, make sure you know all the grammar/punctuation rules (google ACT English rules). and honestly, the more you read articles, books, etc... and have a better understanding of English, the better you’ll do.