RF 24-105mm f/4L IS USM A little loose inner/front tube

[NielsRa]

The front tube move gently side by side - from the lens was new. I thing it is a production fault. 

Can this problem be solved by adjustment or do I need a spare part?

I see another post with the same problem:

A little loose tube: Canon EOS R Talk Forum: Digital Photography Review (dpreview.com)

RF 24-105 F4L barrel loose? : canon (reddit.com)

[shadowsports]

Greetings,

I've never owned a lens with a loose barrel or ring, but I'm sure its possible.  I'd send it to Canon for inspection.  If its new, you can exchange at the retailer.  

[ebiggs1]

"Can this problem be solved by adjustment or do I need a spare part?"

Don't mess with it either return it or send to to Canon.

[Danfaz]

Every 24-105 I've owned has had some play,  as well as 24-70s. They also rattle because of the IS. 

Not sure how much play you are experiencing, but they aren't rock solid when extended, and most likely there's nothing wrong .