People are being extra vigilant because so many people are copy-pasting, and auto-translating. Very often, grammatical errors are a sign of plagiarism, spam, article spinning, etc....

My advice is, just start the article with a brief disclaimer, such as:
"Thanks for your patience. English is my second language".

Please don't give up. Certainly if your content is original, some grammatical errors should be no reason to get any flags.

Good luck.