ABS fluid reservoir

I’ve been seeing my abs light come on on lately for some unknown reason. When I went to check the fluid level i noticed the area right below the cap of the fluid pump/reservoir in front of the passenger side has a thin crack on it, about 1.5", as if like… someone perhaps closed the hood with somethin in there causing the top to be pushed down… and becomin damaged. I don’t want to deal with the hassle of canging it… so is there something I can possibly seal it with??.. or if i would have to change it how would i go about removing it??