similar to 11.1.2.4, each app needs at least 2 ports per application, so in theory, having more than 10 applications in the env can be a cause but I see these errors happening with just 1 app, as other processes would use ports within the hfm port range defined.
I suggest:
Check port range set for HFM datasources > from your message we see it is 10001 - 10020.
Check if you have any non-HFM processes making use of that port range. In case of conflicts, you may need to use another port range for these processes, or redefine the range for HFM.
Other considerations:
TCP Dynamic Port Range should have this HFM port within it.
Each application requires at least 2 ports of the range, so for more of 10 apps running, port range should be extended.
Even with less apps, you can experience issues, cause of time_wait.
similar to 11.1.2.4, each app needs at least 2 ports per application, so in theory, having more than 10 applications in the env can be a cause but I see these errors happening with just 1 app, as other processes would use ports within the hfm port range defined.
I suggest:
Hope this helps, Thanks.