Again, addresses do not expire.

If you are using a centralized wallet or exchange, then they can change which addresses are linked to your account and which addresses you are allowed to use to deposit coins to. That is entirely dependent on their internal database and has nothing to do with the bitcoin protocol. The addresses in question, although they may no longer be linked to your account by the exchange, have not expired and the exchange will still have full access to them.

If you have sent coins to an address which the exchange have de-linked from your account, then your only option is to contact their support directly and explain the situation. Since addresses do not expire, the exchange will be able to access those coins and credit them to your account. Whether or not they are willing to do so is another matter, however.