Had to have my Citroen Picasso's sump re-threaded during a service - should I pay?

I have owned my Citroen Picasso for two and a half years from new. I have just had a 50,000-mile service and the garage phoned to tell me that I might have to have a new sump, as the threads in the oil pan had stripped when the oil change was carried out, and that this was not covered by the warranty. When I reached the garage they told me that they had re-threaded the oil pan but charged me £65 for doing this. Does this sound a reasonable to you?
If the sump plug had ever struck the ground (such as a speed cushion) then it's down to you. If it had been in perfect condition and stripping of the thread was due to the clumsiness of the fitter, then it's down to the garage. But there's absolutely no point in taking a matter as trivial as £65 to the small claims track of the County Court, as that will merely annoy the judge.
Answered by Honest John on

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