Before booking a “no heat” call, a few quick checks can save a wasted visit: confirm the oven is actually set to a cooking mode (not just the clock or timer function), check that the display isn’t showing an error code you missed, and — if you have a double oven — confirm which cavity is actually affected, since the two often run independent control logic.
If all of that checks out and the oven genuinely isn’t heating, that’s consistent with an igniter, heating element, or control-board problem — details worth relaying when you call, since they help a technician bring the right part on the first visit.