Common issue after a power cut
The error code is reporting a fault on the temperature probes in there.
What you can try first if you haven't is turn the main power off to the oven and leave it 30 minutes as sometimes this can do a hard reset on it. So see how this goes.
But if still the same then its either a control board fault or a temperature probe. For this you need to remove the appliance from the unit and remove the top from it and there you can see the control board. On there you will see the wires for the temperature probe. These are thin wires and if you remove the back of the oven you will see the probes there going into the oven cavity at the back.
You need to test them for resistance as they should give a reading in K ohms. If faulty then they will need to be replaced.
But if the temperature probes are fine then the control board is the fault here and would need to be replaced.
But i see you say this is only 5 months old. If so they it should still be under warranty with Bosch so you could give them a ring and they can repair it for free for you.
But if you don't have the warranty or want to repair yourself then you need to do the above I'm afraid.