Is it normal grammarly ruins everything?

I don't know if this is a glitch but it makes it hard to edit. Grammarly has a habit of adding the correction on one line to another. So like say top line correction is "four" not "For" it will add it for anywhere from 2- to the next 4 lines. Even if it makes no sense in that contact. It also will often take out 2-4 words in a sentence or partially remove those words so the sentence no longer makes any sense. For a grammar checking program, this is a pretty shitty one!