Powerblock weights failing!

I have had my powerblock weights for nearly three years and I am very disappointed to see that the welds on one set are starting to weaken and twist. This means that they do not separate properly when I try to choose different weights. I am in the UK and when I bought them I tried to register for the guarantee but was told I couldnt as I wasnt in the US!!

Can anyone advise me on what to do now? They were really expensive and they really should have lasted longer than just under 3 years. I do not know if they can be mended, or who I would even ask to do so. Any advice gratefully received