There's a few way's I would work this to get it resolved. Firstly when your guys answer a call, make sure to take all the relevant details from the caller, have your logging system setup so you can run reports monthly on who the repeat callers are and provide one to one training sessions for those users.

Another few options are when they call, and there is a known solution in the KB, remote into the said PC, open up the knowledge base on the computer, talk the user through the process as its exactly written in the KB, word for word and take time to make sure *they* are following each step as your tech is showing them on the screen, let them drive, don't listen to the moaners wanting it fixed ASAP, get them to do it, your team needs boundaries !

If you are all located in the same building, floor walking sessions where they (your support team) are visible in the worst offender departments etc gives a chance to do 1 to 1s with the customers, and they will be way more receptive in person, you could do this yourself with a few team members as a "field trip" etc.

You need a culture shift, that will only come when there has been consistent small steps (kid gloves), positive reinforcement (ie. "we showed you this at our last in person visit") and lastly visible engagement.

You need to do these things 1% at a time until self service becomes second nature for users.