The first possibility: judicial freezing. According to the judicial ruling, the court staff went directly to the fund company to freeze your account.
The second possibility: the ID number you used to open an account does not match the account name. For example, when the bank opened an account for you, the name was written wrong, or what symbol was used to replace the uncommon words in the name. Now that the system has been upgraded, the name and ID number can't be found. Another example is that your ID number is duplicate with someone else's.
The second possibility is relatively large, especially if you open an account very early, it is very likely that there is something wrong with your name and ID number.
If the above two situations do not exist, it means that the bank staff made a mistake. It may be that the fund is in a suspended redemption state and cannot be redeemed.
I suggest you call the customer service hotline of the fund company to ask.