Meeting Start Date equals to custom DateTime Field Not working

I tried to set up a workflow that if there is change in a custom DATETIME field in Module A (e.g.), it will creates a meeting that has start date and time equals to that DATETIME field. The new meeting is succesfully created, but it does NOT show up in the CALENDAR at all for that new meeting, do you know why??? :unsure:

I notice if I creat new meeting directly from meeting module, it will have some thing like this

But through workflow to create meeting, it does not have similar thing in the scheduling, simply blank