Can you explain the oops? Or are you just looking for specific words?
Because it seems like you're just looking for specific words. Did President Biden, before an investigation, an indictment, or the trial say that Trump needed to be locked up?
Did he lead chants about locking up political opponents?
The best you've found is that Biden said we need to lock him up AFTER there was a conviction. After the Due Process of the Law had been carried out, he said there should be a punishment.