How to find a point of order 8 in Curve25519 or Ed25519?

[qxzhou1010]

I want to find a point with order 8 in Curve25519 or Ed25519. However, I first use Sage to find some points, which order are 8. Then, I using curve25519_dalek::montgomery::MontgomeryPoint to represent these points. I further used curve25519_dalek to verify that the order of these points is 8, however it turns out that the order of these points are all 4. This is bothering me, please help me. I would like to know how to use curve25519_dalek to find points of order 8.