Grammatically errors

Could you please go through my letter and let me know what you think?

We have written to the head of human resources department to terminate her contract for failing to provide her residency. We will update you as soon as we hear back from her. I have heard from different sources that she came yesterday to collect her belongings, but she was denied access to the building. I have sent out an email to members of staff and advised them that under no circumstances should she be allowed on the premises. They should call the police if they see her wandering around the premises.

She has been suspended pending investigation. She has also been warned a few times not to come in to work until she hears back from us. She hasn’t been back since the last time they saw her at the Tesco supermarket. We are awaiting the disciplinary hearing team to set a date so we can inform her. She was a good staff, but I don’t know what really happened to her. She has caused a lot of problems, and I don’t think they will let her come back to work. Everyone wants them to get rid of her because she is a troublemaker. She gets into people's business and doesn’t want to do anything. Instead she will make excuse about her back and feet and that she can’t stand for too long.