Hello there Pal!

I might suggest u to save those values in 2 public variables that holds the starting time value and ending time value of the last time worked, that way u can compare them with the new values of each of the time and then with a conditional, if they are between those values, u can reject the input of the user validating that before they can add that to the function or procedure u will u to suceed this.

this is my suggestion friend!