User Activation Does Not Register User

-- HikaShop version -- : 3.5.1

I've set up an email account successfully. It has been fully tested.

I am able to send an activation link to a new user on checkout.

When I click on the activation link I am taken to a blank page and my user is not registered and cannot continue order.

I am aware I can switch off the activation aspect of registering.

I would wish to know how to fix the issue of the activation link not working.

Thanks in advance

RESOLVED: the Joomla settings (Global Configuration/users/New User Account Activation) was set to "administrator" and not to "self".