Where did you hear it could take 24 hours?
It also means that saying connect to live support can take up to more than 24 hours??
From their Terms and Conditions, it's weird how someone using a site without check and read the TOS first. Does you withdraw a huge amount money? if it's huge then it's very normal since most casinos will need to manual check the withdraw to confirm it's not cheated from their system.
5.1 While Trustdice.win will endeavour to pay out withdrawals immediately, some withdrawals may take longer than others. Trustdice.win shall try to pay out withdrawals within 1 hour, however in some cases, withdrawals may take up to 24 hours.
https://trustdice.win/terms