I saw him on Sunday, but I hadn't spoken with him in any way, shape or form since then. I called him last night with no response.
A good way to get him to call you back would be to word your messages so that the appropriate response to your message would be for him to call you back. Ask questions that require his input. Invite him to something he has to RSVP for. If his guy mind can understand why you want him to call you back, he'll probably do it.
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