I agree you should find a teacher who takes more care with their English.
We naturally say, "She's been trying to contact me." Of course, "she's" could mean "she is" or "she has", but we also know that "has been" is possible whereas "is been" is not. Yes, some native English speakers make this mistake (also look at "would of" or "should of" as another example of this kind of mistake), but it simply means they aren't paying attention. A teacher ought to know better.