If you are an active customer then you will get renewal invoice 7 days prior to your PureVPN account expiry date, which you can pay from your Member Area. By default Credit card (Stripe) and PayPal payments are on auto-recurring, so if you had paid by any of these methods, you don't need to worry, you will be charged automatically and your account will be renewed.
Payments via m Pay, Payment wall, Bitcoin and Ali Pay are non-recurring so you need to pay the renewal invoice manually from your Member Area
Login to Member Area account with your email and password.
Click Subscriptions section, then click Renew subscription button to renew your account.
Select your desired payment method.
You can now proceed to pay and have your account Renewed.