HX711 chip not working
I think in your schematic that you haven't tied AGND into proper GND: -



The above is a sample circuit I found on google that clearly shows that AGND connects to a GND symbol and your circuit doesn't appear to. There may be other errors too but this is the most obvious.

Red box and red AGND are my additions to make it clearer to you.

Here's another schematic that confirms this error is quite common: -



Notice the AGND label on the node that goes to the pin named AGND - nodes that are labelled need to be connected.

Picture taken from this forum that also have folk getting confused about the same issue - node names imply connectivity and, it seems, a few folk have just copied the circuit without looking at the data sheet.

And, if you look at the Sunrom schematic directly above where you picture came from you can see all the 0 volt connections inside red boxes (my addition): -