Hi I'm trying to renew one of our domains for Mobile Joomla Pro, but the checkout button doesn't work on your website, same with buy as well.

Hi, that sounds weird, I couldn't notice any problems. Can you send us an email to /support at mobilejoomla.com/ with some screenshots/video so we can check it out? Also could be great if you could try with another browser if you didn't already. 

Thanks
Miikka

Just trying to screengrab what it is and realised it's related to the VAT No. when purchasing as a business.

If I choose personal under Purpose which has no VAT option I noticed the check out button is active.

As soon as I select business it requires a VAT number and the Check out button won't activate until a valid VAT number is supplied, leaving blank isn't an option.

However regardless of how I format our VAT number ie. with or with the GB prefix it says Invalid or not registered underneath and won't let me purchase?

Ok, I see - it could be a temporary issue with the EU VIES VAT API. You can try again, but if it still doesn't recognize it, please send your VAT ID to me and I can come up with an alternative. Thanks!