As a past person, I just want to say that don't replace the official default source with Tsinghua source or other domestic sources, just use the default official source, because the packages of Tsinghua source are all old, sometimes not only do not upgrade the package, but downgrade package, this is a pit. Of course, if you use the default source download speed is not fast, then change to the domestic source, but you have to endure the troubles of the old package.
If you have used Tsinghua source or other domestic sources, the following is the command to restore the default source:
conda config --remove-key channels