The timer suggestion above is a great idea, but over the years I never had any luck with those mechanical pos dial up timers, at any price paid

They either don't work, stop working, fall apart, the switch seizes halfway during the STOP cycle and fries itself, cut fingers stuffing about with the preset click in crappers,
dramas with which way is ON/OFF, the sound resembles a bomm about to go off at 'any minute'

etc etc
and for the advanced snafu enthusiast > the pos refuses to be re-assembled, once the issue is confirmed unfixable aka not worth re-engineering it
the digital versions are just as bad, they offer the frustrated user different problems
basically timers for me are a reliable bad news affair
It should be easy but it never is, and every few years I get pulled back in for another rebadged money wasting serve