The engineers have their own tasks and deadlines to deal with, why are you talking to them directly to get the information you want? You need to talk to their project manager to either give you access to the database in question, write a tool that generates the report you need or write a one time query to get this information. All of these things take time and need to be planned and resourced. I hope you’re not just walking up to people and asking for random lists of customers that ordered more than once in the last year or whatever?
You should probably add some specifics, because your original post is super vague.