Speed limit not works

There are no speed limit works while internet backup
I set 20 Mbit/s in Settings-General-Internet, but no speed limitation - backup run on total speed of 50 Mbit/s.
see Attachment

I see that average speed is near 30-40 Mbps.
Try these settings:
Total max backup speed for internet connection: 20480
Max backup speed for internet connection: 10240
Ensure your client uploading in 10Mbps
Then try to raise values.