u/ConfectionFar7137

I checked my grades today and for Human Communication I was supposed to get an A no doubt but instead there is a C. Even in blackboard it shows 91% which is an A. Is it possible that my instructor put in the wrong grade? I emailed them but they are a part of the strike so Im not sure if theyll see it. Can final grades be changed months later? Im just worried it might reach a point where the grade cannot be changed.