Doesn't work in the UK like it says Rated 1 out of 5 stars

This doesn't seem to work in the UK like the information suggests. I cannot find any UK store which has any codes, eBay, Amazon, large department stores, nothing! There is no Market option for the UK in the options so it doesn't look like there is any support despite there claiming to be. I have tried it on USA stores and the browser bar did shows coupons available so the extension is working. Please fix the details so people don't waste time on extensions which are of no use in specific locations.