Not able to upgrade to Pro

Hello,

I am trying to buy a Looker Studio pro subscription. when i land on the Looker Pro page, i get a message

Could not connect to server. If the problem persists, try again in a few minutes.

I am using Looker Studio for a while without any issues.

How do I buy Looker Studio Pro subscription?

Any help in this regard will be of great help.

Thanks,
Vishwa Kumar