Engen Fuel with water contamination

I'm honestly disappointed with Engine. I put fuel in my vehicle at the Sonnendal service station and a few km's after my car started jerking. I called the service centre and spoke to the Manager Jonathan who was pretty dismissive of my problem. I then took my car to have it checked and it was found that there was water in my fuel filter. It was then decided to use dry fuel to remedy the issue (however this was after a week of driving a misfiring vehicle). I now contacted Jonathan to inform him that water was found to be mixed in with the fuel to only be told that I should have kept samples for them to test. My argument is, why did Jonathan not inform me of this procedure initially especially when I told him I had no issues prior to fueling up. As of now, my vehicle is fine but I am left with a sour taste in my mouth because of the expenses incurred to purchase a new fuel filter, new spark plugs and dry fuel, not too mention the waste of fuel (driving a misfiring vehicle etc)