Its very hard to fix for most clients. They come from the perspective that something is wrong on your end, they are paying you and you need to resolve it.
What we do is talk about what happened which 90% of the time will fall on deaf ears we will also send documentation if we have on that issue. We will create documentation if it's a reoccurring problem, this never gets read.

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What we do is we have a set amount of monthly time for support not relating to issues on our end. When this time is used up we will quote to repair the issue.
Most people are fine with this, to be honest, those that aren't realize that now there's money at stake they will give that documentation a shot. If they get back to us saying they've tried the docs and still didn't succeed we will remote control with them and walk through step by step since they are now more willing to listen. Yes it costs us a bit of time now, but in the future, it saves us a ton more time. While also empowering a client solidifying our relationship.