Your Total Balance shows the full value of funds in your savings account, while your Available Balance shows the amount that is currently available for you to access or move.
Your Available Balance could be lower than your Total Balance if some of your funds are not yet available, for example;
Interest accrued for the month
Funds that are currently under notice.
Funds held in a savings account with access restrictions.
The difference between the two balances therefore reflects funds that form part of your savings account balance but are not currently available for you to access or move.