Vivaro little puddle in back of van footwell

i keep getting a little puddle of water in the side loading door footwell, thought it was my equipment leaking as I'm a window cleaner but it can't be I havnt worked all weekend and I dried it up on Friday, checked it this morning what do you know a little puddle, the rubber seal looks a little worn and knackered that runs around the body of the van, or will it be the seal on the actual side loading door, or could it even be the back doors and then it's running to the footwell....

This a...

Vivaro little puddle in back of van footwell