Upgrade Store
From Shopnix Help
What is Upgrade store ?
In order to receive the uninterrupted service you have to renew your subscription.
Where I will get Upgrade store feature?
When you enter to the store admin ,at the top you will find a red color message line like below
just click on that message and you are redirect to a new page like below
Carefully read all the information then choose your plan click on the
you will redirect to the payment page like this
Fill up the desired fields.