It happens occasionally, that specific ERC20 token at certain point in time migrates from Ethereum Blockchain, where it exists as an ERC20 token to own blockchain. This happened for example with TRON, BNB, ICON, VECHAIN and EOS in the past.
In such case you have to follow the transition advice of the specific token issuer.
TRON - https://tron.network/trx
You have to be careful though not to mix up legacy ERC20 Tokens and own blockchain coins under same name!
You can not store native blockchain coin in ERC20 wallet and vice versa!
For example with TRON (TRX) you can distinguish the two by the format of the wallet address:
Legacy ERC20 TRON Address - 0x939a715B25308f56Ed17Fa60fC88556E77B83602 (Ethereum address format, as all ERC20 tokens reside on Ethereum blockchain/wallet)
TRON Blockchain Address - TF5ko6qZ7dQPaPNhNyurgL8RcYeB8MQXeh
Tokens that will be migrated to own blockchain will be removed from BC Vault GUI in some time (you can always add them back as a custom ERC20 token, should you wish so).