Problem updating items

So, I've been having trouble doing multiple update commands in one email. I'm not sure if this is a design, or if I'm experiencing a problem. I told Sandy to lookup entries from a 2 week period and then I wanted to update several items as "archive" and several others with an updated date.

I replied to Sandy's list with the following:

u #1 @archive
u #2 @archive
u #3 monday
...

Well, in every case (no matter than I had Sandy's email settings to html or plain text), Sandy only saw the first update command.

So I had to send 6 different email messages to update 6 items on the list.

Ideally, I could say U 1-10 @archive, but failing that, I thought I could just put each command on one line.

If I have to send several separate email messages, this might be really cumbersome.

Am I doing something wrong? Any suggestions?