Yes, the Helo Health Shop allows this operation, but if you decide to purchase a new Wellness+ subscription with the same account, while the current one is in Closed status, it will start immediately, terminating the previous one. 

When you close the Subscription, you only switch off the AutoRenew function on your Subscription, but you will still benefit from its services until the end of the month (30 days from the purchase day), even if it shows as Closed, unless a new one is activated.