Why can I not upgrade my iCloud storage? If I try to buy more storage the system walks me through the process and when I say buy it just cycles back to the original upgrade screen and the request does not go through.

I can not seem to upgrade my iCloud storage to accommodate Photo library. When I go through to process to upgrade storage it walks me through the process but when I click the BUY button it processes for a couple seconds and returns me to the upgrade screen without updating my storage. The only thing I see different in the screen is a small padlock icon in the upper right corner of the window. If it is locking me out how do I unlock the process?

I have tried to upgrade from my laptop, my phone and my iPad no luck.