Paypal- "Return to merchant" error

I don't understand why i'm getting this or what this means when i try to check out.

I have a regular free paypal account that I've had for years. I simply added an email address to my paypal account that I want to use for my store and then entered it in the "email" field in the paypal setup options in Hikashop. Do I have to change my paypal account to something different? I looked under merchant services and saw "website payments standard", is this something I have to use?

Another thing I noticed is that the page is displaying the email address instead of the website address. I have a logo loaded in joomla and entered that url into "paypal header url", but it's not displaying as you can see on the screen shot.

Thanks