This is expected behavior. To reduce transaction failures, some sell orders are processed in USDC on Solana. If you see a USDC balance on Solana in your portfolio, you can convert it to USDC on Base directly in the app:
- Go to the USDC tab.
- View or Tap your USDC (Solana) balance.
- Select Convert to Base.
USDC on Base is the standard currency Ulys uses for trading and in-app balances.