What is meaning of animation blend space 2d red area?

Development Character & Animation
,
1

capture
capture1405×564 37.6 KB

What is meaning of this red area?
and
should I fix it?
if answer is yes so how to fix it?

2

Automatic Blend Space Creation in Unreal Engine | Unreal Engine 5.3 Documentation

yes I was stupid I must read this doc