How to downgrade from Economy to Premium subscription ?

Now, my plan is Economy.

I would like downgrade to Premium.

How can i do? and Can i get refund?

 

Thanks 

You can easily do this from the Account > Billing section, please select the Premium plan and click on Switch Plan, as explained in the picture:

Can I get refund different amount?
...

As you have purchased your plan over our Stripe payment processor, you should automatically receive a prorated refund of your unused plan while switching to a different pricing plan.

Please let us know if you need further assistance, or if the difference in amounts is not automatically refunded, and we will be happy to take a look into it and assist you.