have you tried the EDIT>UNDO function?
as long as you have not saved it and closed the project the undo function should still be an option.
In my experience, in working in a project, every now and then I will inadvertently delete a clip or drag a clip a bit making it out of sync.... rather than trying to drag it back I simply use the EDIT>UNDO and waaa laaa, it's back to where it was supposed to be. This works fine up until you save and close the project. Then, apparently, Sonar wipes the undo for that project session from it's files.... at that point, next day for example, if you discover the mistake.... ouch.... the undo won't work. It's either try to fix it, or grab the mics and do a punch in recording session.