Install error `paragonie/random_compat`: `package is fixed to v9.99.100`

[Commifreak]

Problem 1
    - 2amigos/2fa-library 2.0.0 requires paragonie/random_compat ^1.4|^2.0 -> found paragonie/random_compat[v1.4.0, ..., v1.x-dev, v2.0.0, ..., v2.0.21] but the package is fixed to v9.99.100 (lock file version) by a partial update and that version does not match. Make sure you list it as an argument for the update command.

There is already 9.99.100 but your composer says 9.99.99. I believe, you should use ^9.99.99?

Why is the versioning 9.99 by the way? There are 1.x and 2.x trees, what is the 9.99 tree?