POS amount how to track

i have one question in POS
suppose user ‘A’ shift start that time he have openinig amount is 0 and at end of the day he submit all entries of 50,000 and now his shift is end another user ‘B’ start shift user ‘A’ give amount of 1000 to user ‘B’ as ‘Opening Amount’ and reamining amount transfer to bank account or do any other so my question where we track remaining amount