Cannot find "install new module" button

Dear guys,

I have googled around and checked that

1. I am using the node 1 user and also set as administrator

2. I have already enabled “update manager” module

3. I have already cleared cache of my browser

I am using D8 on acquia cloud site (trial version yet) and I could not find the “Install new module”  button on Extend page.

I also tried to go to /admin/modules/install

It said access denied as I am not authourized to access to that page. However, I am using the node 1 user account and set as administrator…

What should I do….

Many thanks

Jen

Drupal version: 


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