When you reach your credit limit on credit card is that amount renewed after youve paid the balance?

For example if you have a $300.00 credit limit and you have used the $300.00 and youv'e paid the bills on time does the $300.00 get renewed each month or after you've paid|||Once you pay the balance off, then your 300 will be available for use.|||AFTER you pay the balance off. You can never have a balance greater than 300.