Does your VFD that you where looking at have a molded 3ph rectifier body, if it has you can't see how the module has been configured inside, we all know what a normal bridge full wave rectifier looks like but most of these are not a normal configuration inside
Most VFD Drive Manufacturers, have a lay out drawing that looks like this below, that clearly show how they want the user to connect the 2 or 3 input terminals, try connecting the Neutral wire for single phase to L2 ( S ) Terminal, and not to what the manufacturer spec's, as below, many have done this, only to damage there expensive VFD Drive, this example is only one configuration, so anyone wiring a VFD should wire to the Manufacturer's requirements and not here say, or from a video they saw on YouTube