Can’t change from Sandbox to real paypal

Hi there

I have finished testing my shopping pages and I now want to enable paypal express for real however it keeps defaulting to the sandbox paypal.

I have in checked the use sandbox tick box, cleared the cache and I also tried on different browsers to no avail. I also activated standard paypal and that works fine it is just the paypal express.

I must be missing something obvious, can you shed any light as to why this might be?

Thanks