Family drama !!!!

So my mom had 5 girls we all grew up really close , okay recently for about six months I’ve been having issues with two of them , one younger and the oldest .me n my oldest never had a great relationship like that but we were working on it however the younger one we have had a great relationship growing up and now I’ve been trying to reach out to her n she never responds idk what to do any more ... should I keep trying or let it go ?? I did nothing to her and she acts like she hates me