How to set up miniconda3 at HLRN

Hey everyone,
are there any tricks to install packages with conda at HLRN? I am not sure whether it should work or not. I know I thought about this a while ago but I forgot the conclusion... Anyways, right now if I try to follow the instructions of the readme, the following happens (also when I try to use the remote_jupyter_manager.sh):

bdata1:~ $ source miniconda3/bin/activate base
(base) bdata1:~ $ conda install jupyterlab nb_conda_kernels
Solving environment: failed

CondaHTTPError: HTTP 000 CONNECTION FAILED for url <https://repo.anaconda.com/pkgs/free/linux-64/repodata.json.bz2>
Elapsed: -

An HTTP error occurred when trying to retrieve this URL.
HTTP errors are often intermittent, and a simple retry will get you on your way.

If your current network has https://www.anaconda.com blocked, please file
a support request with your network engineering team.

ConnectionError(MaxRetryError("HTTPSConnectionPool(host='repo.anaconda.com', port=443): Max retries exceeded with url: /pkgs/free/linux-64/repodata.json.bz2 (Caused by NewConnectionError('<urllib3.connection.VerifiedHTTPSConnection object at 0x2aaaae3cccf8>: Failed to establish a new connection: [Errno 113] No route to host'))"))