A beep can acknowledge an input or reject it. The display message and the appliance's current state explain which meaning applies.
What the observation means
A lock, incompatible mode, active programme or temperature restriction can prevent a new selection. Repeated pressing does not remove those conditions and can hide the original message. Look for the exact word or symbol shown after the first rejected input.
A useful next step
Check the permitted sequence in the manual. Record which setting you were changing and whether the oven was already hot. If normal allowed inputs are still rejected, preserve the message for assistance instead of repeatedly cutting power or guessing button combinations.
Manuals and supporting guidance
Model-specific instructions take priority. These references support the practical principles discussed here; they do not diagnose your appliance.