Reasons for holding advertising money:
The card has been added to too many accounts that owe money to Facebook, this will cause FB to mark the card and hold your card money for the next addition.
Invoicing failed. During the process of running ads, there will be many cases of unsuccessful payments. A few times like that, FB will also hold your money even though it didn't before.
There is no money in the card
Payment card provided by the bank
Because the advertising account is not healthy enough
Please pay attention to these things to avoid holding money next time