Loading tykky will unload all the modules already loaded and will prevent you from loading new ones. This is done to avoid potential conflicts between packages installed in your environments and those from the module system (eccodes, ecflow, compilers, etc.).

To go back to the module system, use the reset command:

module reset

Simply unloading the Conda module won't be enough to go back to the defaults state, many modules won't be visible. It's best to reset the module system.