A phone call is best. In business and family life, I learned long ago that some questions which spur endless typing back and forth can be resolved easily with a 2 minute phone call. At work I have the rule that if I can’t type out the question in a minute, I should call instead. Even if the question is extremely complicated this works. I call and say, “Hi, this is my question and this is what I want. I will email you more details. Thanks, bye.”