The cause of the problem is that the spark module does not sense the flame when it's on. The spark igniter is also the flame sensor which provides feedback to the spark module.
Make sure the igniter is properly aligned with the burner lighting holes and it is clean. All eight lighting holes must be clean too. You can enlarge them using a drill bit one size bigger.
If it would not fix the problem, replace the bake burner and the igniter.
There is a small chance for the spark module itself to be bad as well.
- The igniter
Part number: 9758079 
- The bake burner
Part number: 9758078 
- The spark module
Part number: W10331686 
Here are the breakdown diagrams and
Replacement parts for Whirlpool SF369LEMQ1 30" GAS FREESTANDING SELF CLEAN RANGE SEALED BURNER | AppliancePartsPros.com
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