module "pages/index1/hanzi-writer-miniprogram" is not defined

[XinwenCheng]

Followed instruction part of Doc as following:

But when I try to preview my mini program, there's an error as following:

index1 is my current main page, and I'm pretty sure hanzi-writer-miniprogram was installed currectly.

Not sure why it checks plugin under index1. Could anybody help? Thanks in advance!