If the update installer is unable to download the needed files to install the update, it will fail with the following error message:
Failed to download release data
Something unexpected occurred.: This is not common.
To resolve this issue, contact Technical Support.
Update session complete.
You can look into the connection error using the article below.
Why do I get a connection error when installing or activating MATLAB or another MathWorks product?
If the network issue cannot be resolved, you can install the update manually with the offline installation files using the following article.
How can I download and install a MATLAB Update manually?