To find the right part & fix

Brand: Whirlpool
Model Number: WFE51S0EW0
Main Symptom: Front right cook top is not working
What happens & when: From past few days the right front stove is not turning on, when we turn on the switch ‘cooking on’ & hot surface’ light/indicators are turned on, but there is not heat from the stove, all other elements are working. we also noticed few days ago that this cook top was behaving inconsistently like when we reduce the temperature it still goes on high level.

I wanted to know what is the possible issue & which part is required to fix this.

Error Code (if any):
Parts or tests already tried:
Photos / video link:

I would suggest using a multimeter & checking the infinite switch for the burner not working. Ensure you have 240VAC into the switch on L1 to L2. If you do, then turn the switch on and check for power out (240VAC) from the switch on H1 to H2.
See link for additional info: https://www.youtube.com/watch?v=b-p2GQgA72Q

I Checked by switching the wires on other knob & the burner/coil lighted up, it is the infinite switch issue. pls suggest me the right part to replace.

Thanks

I replaced the element switch & now the burner turns on, but after few seconds it loses heat & turns off, if i turn the switch to 50 % it on’s for few seconds & turns off, when I increase the switch again to 100% it turns on, but turns of again after few seconds, what could be the issue ?

it is faulty switch again ?? pls respond