I have the same problem with our whirlpool double oven. While in the middle of baking bread the control panel went blank and the oven no longer functional. I left the oven alone and in 15-30 minutes the digital clock reappears with the Code E6 F2. When I push turned off the code disappears. When I tried to turn the oven on again it worked and then the screen went blank again after a few
minutes working & then the oven didn't heat and the screen went blank again. s it the control panel? Please help.

Here are your parts
Parts for Whirlpool RBD305PDQ14 Wall Oven - AppliancePartsPros.com

See the attachment for the tech sheet

This is difficult to trouble shoot as the error is related to the control panel keypad. Also it may be related to the unit heating up and causing a bad connection.

I would try the following first as it may just be a bad connection.
If that does nothing I would replace the control board.
This is a gamble but it is the most likely cause.

Connector Cleaning / Checking
Unplug the unit
Open it up
Remove the ribbon cable from the keypad to the control board at the control board.
Clean the edge connector. Use electronics contact cleaner or isopropyl alcohol.
If it is the type where there is not a connector just the insulation is removed, it can be cleaned with a pencil eraser. Do not use an ink eraser as it is too abrasive.
Check the tracks in the ribbon cable for hairline cracks. A magnifying glass helps here.
Would not hurt to clean the connector on the board. Use electronics contact cleaner or isopropyl alcohol and a tooth brush. Be gentle and do not reconnect till all the solvent evaporates.
Reconnect everything and give it a try.