unable to use Goole play store

I tried to buy Nexus 7 from Google play store. I went through the process till the last step showing google wallet, then the process froze, and I could not go through with the purchase. So I tried again with my desktop machine, and the same thing happened again. Google may be the leading search provider, but they are lousy shopkeepers!! There was no way to remedy the procedure. No option to cancel and try again. I tried to enter nil in the quantity thinking it will cancel the purchase and start again. Alas it did not work.

Go to Carphone Warehouse. It will cost you less.

Many thanks. Alas I wanted the version with 3g which carphonewarehouse do seem to stock. I have been buying goods online for years. I never encountered a system like google play store.It is appaling. I gave my details, credit cards details, then before the caption when one press for the order there should be another caption which appears and quickly disappear in a fraction of a second, which I think is causing the problem. And for this to happen on my laptop and desktop is ludicrous.