Step 1: Login in your client area.
Step 2: Go to, My Products & Services and here all of your services will be listed.
Step 3: Open your VPS hosting Service.
Step 4: Now, scroll down and you will find the following:
Step 5: Either use can use the above or else you can also use the below to send the reboot command to the VPS.
Note: If you don't find this option under your product & services. Kindly open a support ticket.
That's it !!