I get the same thing. I purchased bnb2 via the trust wallet app via 3rd party. Bnb2 showed up. When I try to swap to bnb20 it says exactly what you said. “Insufficient funds”
Figured this out. I stupidly didn’t leave enough BNB in to cover fees. So lower the amount requested, might help. Worked for me.
Can someone remind me how blockchain is the most secure method to invest our future financial system on?!