"Create new Backing Store" option not working ("Create new BucketClass" page)

[SanjalKatiyar]

Go to: "Storage > Object Storage > Bucket Class > Create Bucket Class > Select "BucketClass type" as "Namespace", type any "BucketClass name" and select "Next" > Select "Cache NamespaceStore" as policy type and select "Next" > On the third "Resources" step, select "Backing store" dropdown and click on "Create new Backing Store" item"

No modal pops up, whereas on clicking "Create new Backing Store" item from the dropdown should open a modal.