Sometimes when I ask for a font I don't get any reply at all.
I don't want to post it again so that it doesn't create spam, but I also really want to know what the font is.

Any advice?

You can bump the original post so that your ID request will be brought to the top of the list. You bump a request by replying to that request. Most people just put BUMP as the message in the reply. Although there is no limit as to the number times you can bump a message, it is advisable to give ample time between bumps - perhaps a few days or a week