Moca Problems

Looking at https://www.actiontec.com/blog/moca-vs-wi-fi-for-live-video-streaming-to-youtube-twitch-facebook/, it isn't clear whether the cable modem is before or after the MoCA adapter.  It just says 'connect your cable TV wiring to the coax IN connection'.  It does say that some cable services are MoCA ready, but to check with your provider.  I would think the modem would be BEFORE the MoCA adapter.  Have you tried that?  Also, you might need a signal generator to test whether your in-home coaxial wiring is intact.

You could always get a short coaxial cable (to simulate your in-house wiring) and test your connections in the same room.

@jav6joev  is correct. Your upstairs config is setup wrong. And the Point of entry filter should be on the input of the first coax cable splitter in the line.

@norolova The connections you have sound about right.  I'm not clear if you could loop the coaxial through the TV/STB Out and into your modem.  However, if you don't have an issue with your Internet then it sounds like the Actiontec MoCA already has a built-in MoCA Splitter.  So the issue might be your coaxial wirings (inside the walls) are not network within a MoCA splitter.   Here are some quick tests you could try:

Test 1 - Verify if the MoCA adapters can link directly to each other

1. Connect a coaxial cable from the MoCA adapter 1 to the MoCA adapter 2
2. Verify the Coax/MoCA LED on both adapters are ON
3. If so, then they're paired and linked with each other 
4. If not, then they're not paired.  Try to re-pair them by press-and-hold the pairing button (see user manual or contact support) I think it's "MPS" for the Actiontec MoCA ECB series

Test 2 - Verify if the MoCA adapter can link from one room to another room

1. Connect MoCA adapter 1 directly to the coax port from the wall in Room #1
2. Connect MoCA adapter 2 directly to the coax port from the wall in Room #2
3. If the Coax/MoCA LEDs are not on, then it's likely the coaxial wirings in the house are not joint 

In order for MoCA to work in your home, the coaxial cabling must be network in a "Home Run" method as suggested by the MoCAlliance. Refer to this link for best practices http://mocalliance.businesscatalyst.com/technology/Final_Best-Practices-for-Installation-of-MoCA_170516rev01.pdf.

Try the following 2 steps 

1.  Find the point of entry for your Comcast service and exam the coaxial wirings to the rooms.  It is usually in the garage, basement or attic.   If all the coaxial wires are routed through a coax splitter then that's a good start.   
2.  Make sure the coax splitter used is MoCA compatible.  That is the frequency supported should support MoCA range from 1125 - 1525 MHz.