You need to verify that the address formats are compatible when making transactions with your crypto assets.
In this situation, please verify your BTC address format:
- Legacy address format starts with "1..."
- Segwit address format starts with "3..."
If you sent BCH to a BTC Legacy address
You will find them in your BCH main account, if you sent your BCH to a Bitcoin Legacy address.
If you sent BCH to a BTC Segwit address
Your BCH are stuck as Bitcoin Cash doesn't support Segwit. However you can use this tool to recover them.