My bakery is trying to transition from a conventional oven to a gas
commercial convection oven.

Our cakes are all coming out overcooked on the outside with an undercooked
inside.

The ovens are used and have not been calibrated. We don't know if they are
working correctly. Cookies seem to come out fine using the ovens, but all
of our cakes have come out wrong.

We have been forced to use our conventional oven for now, but because of our
volume, it's very hard to do so.

Any hints would be appreciated.

Thanks.