Payment Table step not working

Hi .. i need your help please asap. I have setup membership 2 and my registration process is not working on a live site.

Step 1: Create an Account seems to work ok. The WP user is created and an email gets sent to the user.
Step 2: after account creation the following url loads ?action=register_user&step=payment_table&membership_id=xxxx HOWEVER just the Create an Account form is visible .. not the option to choose the membership or make payment.

UPDATE: a possible clue from error logs ..
PHP Fatal error: Uncaught exception 'Exception' with message 'Invalid Membership.' in /plugins/membership/app/model/class-ms-model-invoice.php:783

I look forward to a speedy response :slight_smile: