Invalid address when selecting paypal

Hi - 1st post here. All was going well until a few days when people stopped buying and emailing saying there is an issue with the website.

So after selecting paypal at checkout and clicking finish, the user is directed to

www.1stproengineering.com/component/hika...checkout/step/step-1

Where the following error occours:

0 Invalid address: 1st Pro Engineering

Was working fine until a few days ago - any ideas?

Thank you

We had this same problem when Joomla 3.5.1 was released and Hikashop 2.6.2 update solved the problem
Now we are at 2.6.3 and the problem has come up again in our development server, not a huge problem now because the production server is working fine, but at some point it could become a big problem

Tried the latest update com_hikashop_business_v2.6.3_2016-06-09_14-13-25.zip, I checked that it updated some more email sending code but the issue is still present in our development server

Please help