Calling all hairdressers!!!šŸ’‡šŸ’‡

My step mom put a maintamer in my hair a month or 2 ago, hell maybe 3 months ago and my hair is almost impossible to brush out now and has been since that night!! It's course, dry, and very tangly. I've deep conditioned and every thing. What else can I do to help? Is this normal? It hurts so bad to brush out and takes forever to brush. It's a nightmare!!