If you were served with a "criminal trespass warning", then it is just that----a warning.  It is not a charge.  It is not a conviction.  It is not on your criminal history record.  Only that agency keeps a copy in their files.  You will only be arrested and charged in a formal court if you violate the "warning."  Think of it like a traffic ticket warning.  If a cop issues you a "warning ticket", then your insurance doesn't go up, you don't have to pay a fine, and you don't have to go to court.  The agency will note they have warned you.  If they pull you over for speeding a second time, then the law enforcement agency will officially charge you such that you would be charged, have to pay the fine, and appear in court.  Criminal trespass warnings work the same way.So.....first step, is just to keep calm.  It will not hurt your employment.  Stay away from the area where you have been asked to stay away from....and then everything will be fine.  Even if the owner says "never mind...come on over," still stay away.  Even if the owner/alleged victim says it's okay, law enforcement can still arrest you if they catch you in violation of their warning.