By default address wont expire, But its an feature or limitation enabled by wallet custodian for their wallets.
I have already shared one of the examples where the custodian support acknowledges the issue, otherwise they wont.
I have seen some other wallet custodians also having this expiration on their wallets address.
If you are not frequently using that custodial wallet you might contact the support, but I never heard about the limitation of inactivity will be expired. This is the reason why I didn't hold my coin for a long time in any custodial wallet, it will take time to contact the support for the reactivation of your account if you are using the email address and phone number verification, make it sure still you can access on it.
They were right, once Bitcoin address was generated upon making a Bitcoin wallet. It will never expire or either vanish. Even the chances of having doublicate address, it wont happen. So, there's no reason your Bitcoin address will be expired, as long as you have keep the private key and password, you can restore it anytime.