question

Refer to the limits listed in Development Mode - PlayFab | Microsoft Docs. The limits for Unique Users, Profile Storage, Content and Configuration Storage will not be reset, and other limits will be reset monthly.

If the monthly limit has been used up, you will not be able to use related functions during development until the limit is reset next month. If the limit such as Unique Users reaches the upper limit, then you need to upgrade the account to a paid plan, and then launch the title to lift the limit. Of course, all of the above limits will be lifted after you launch the title to the live mode. You can refer to Account Upgrades - PlayFab | Microsoft Docs for account upgrades and Title Launches - PlayFab | Microsoft Docs for title launches.

You can add a credit card when you upgrade your account to a paid plan. You can also add a credit card in Game Manager -> [Your Studio] -> Billing Summary -> Billing Information.