2015 Vauxhall Vivaro pulling to left

Check the air in the types.

With vehicle of that age you have to pursue dealership to rectify the fault under warranty .Try contacting VW customer services if still getting no where , but don't give up .

Could be any number of things,
I'm not interested,
YOUR not interested in the cause either,
And it seems that neither are the agents.
So give them a last chance AND tell them if not repaired you are going to book it in to your local steering specialist to check every aspect of the vehicle,
AND THEN BILL THEM.
My local guy has this high tech laser beam 4 wheel alignment jig.
not a set of front wheel gauges.
But this isn't cheap.
Oh and back at the agents you can wave around the phrases "construction and use" and "fit for purpose".
which your van clearly isn't.
I mean c'mon this van is so new it still has the wrapper on!!

Good advice 1/4 drive but doing that gives them an out to wash their hands of it due to the fact you have used an outside source and a reason to refuse to do it under warranty .The could and will say they don't know what the other garage did and whether they introduced any further faults .Having ran one of the biggest UK VX dealerships , believe me that was a godsend to getting out of a problem car !!! that and " my mate done / said this " Wheel alignment should not need done the numbers of times yours has , unless wrongly set up .Would have thought the dealership had the latest gear as it was part of the deal you had to keep up to date with latest tools and equipment .Either that or sub contract the geometry check out to specialist .Could also try another dealership for a second opinion .

Granted.
And to clarify,
My advice is book it into a 4 wheel steering specialist for CHECK,ASSESSMENT AND REPORT on any and all probable causes for steering fault.
NOT REPAIR.
explain your situation to them.
So then you have a headed paper report to show the agent.
Or if it comes to the worse a document for legal department.

^x2. You can never have enough written reports / evidence to back up any possible problems down the line .Also dealership visits on complaint will be logged in car history if needed .

just an update (NOT A SOLUTION)
been in touch with customer services etc and had van booked into a different vauxhall centre for investigation work.
had tracking set to factory settings and guess what... it still pulls to the left. the official wording was "it has a biase to the left". mechanic said he'd accept the pull himself. and that if you have both hands on the steering wheel as required by law you don;t feel it much anyway.

what a thing to say????

not finished with them yet. will see what customer services say and then on to legal business

Not a solution but I had a new Sportive in July been to my dealer twice now next visit this week is for some test thats not covered by warranty and they want £50 to do it. They checked tracking and that is spot on but still pulls slightly to the left as it has since I fetched it.

Radio is the other problem as it keeps going off sometimes for seconds sometimes for several minutes. Vauxhall know about this but don't have a fix. Suspect they need a young teenager