Solving environment: unsuccessful initial attempt using frozen solve. Retrying with flexible solve.

[amirasrasami]

When I am trying to install necessary packages with conda install cfgrib cartopy casadi scikit-learn -c conda-forge
Here is what I get.
Collecting package metadata (current_repodata.json): done
Solving environment: unsuccessful initial attempt using frozen solve. Retrying with flexible solve.
Solving environment: unsuccessful attempt using repodata from current_repodata.json, retrying with next repodata source.
Collecting package metadata (repodata.json): done
Solving environment: \

The last "Solving environment: " runs indefinitely.

[Junzi Sun]

i recommend to use mamba instead of conda