Someone just get this same issue fixed recently and it's related to blockchain all he had to do was import is BIP39 mnemonic phrase into his Electrum wallet just as Charles-Tim replied You can check link for fixed similar issue https://bitcointalk.org/index.php?topic=5491977.0
This solved a different problem which was that the balance is there but the transaction fees are high and because blockchain.com buggy you cant send from that wallet.