It all depends you who the MP is, mine made me come in to his office because there is a form that needs to be signed, some might not get this form signed by you and just do the inquiry with your e-mail request. I was just telling my personal experience and what my MP told me. He said that the first time I need to sign a form, so I need to physically come into the office, but each
additional time after that I can just e-mail him. It will vary from MP to MP. The best way to find out is to give them a call.