Your contract is with the people you purchased the Disgo from and you should really be talking to them about the guarantee. It may have a design fault that you are unaware of did you perhaps drop it on the buttons? If it is a known design fault (have you Googled to see if this is a common problem?) then the damage will be covered by the guarantee but if it is accidental damage you may not be covered. Talk to the supplier about the guarantee terms.
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