Eng - 問 In the meantime 同 In the meanwhile 的分別

Dear Writing Experts,

In one of my personal writing, teacher commented that I have been incorrected use of "in the meantime & in the meanwhile, could you explain the sentence use.

My sentence is:

This promotion aims to maintain close interactive communication with you, our valued coustomers and potential customers. In the meanwhile (correct me as "in the meantime"), as a five star hotel, this give us the chance to learn about and cater to your special need.