Your tortoise wouldn’t eat once a day in the wild, it would graze all day. Give it access to food all day. Most people start with a pile of food as big as you would need to fill up the shell. If there is extra at the end of the day feed a little less. If there is none, feed a little more the next day.
I put one pile in there in the morning for each after their soak since I know they'll be hungry and they eat on it all day in addition to what grows in the enclosure. I take it out when lights go out.