Custom Randbetween that only changes once a day

We are currently utilizing Power BI as a makeshift inventory management system and with said system, we have a list of accounts that are assigned per individual.  The way I generate the assignments is by using a simple randbetween formula and then assign each individual a number.

The problem with this is that I would like to be able to use our auto-refreshes during the day but I don't want the randbetween to change throughout the day.  Meaning the inventory for the person does not change until the next day.  I am not for sure if this is even possible.