If there isn't an answer that is good enough to be best answer, you could write one yourself if you've found a solution, but it may be better to do so in a way that prompts someone else to give a good answer.
Marking your own best answer probably won't earn you anything, so it's better to give someone else the chance to do so.
@tim1974 I couldn't agree more. Why should customers feel that they have to come back to the giffgaff website, log in and say thank you by awarding a best answer?
It's a pain in the bum, much like leaving feedback on eBay. Some people will understand the concept of this community, but given that most customers do not, why should they bother?
I've called various networks' call centres, and I don't ever feel the need to call them back and thank them when something works. When something doesn't work, then you'll return to get more answers (or have a rant!).
Of course, all this depends on whether the answers that you've had as a customer can really be called best answers.
However, each to their own.
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