I attended Google phone screen interview for the Warsaw location. Below is the question

There is an directed graph with node as below
Node { int value; List outBounds; }
Multiple nodes can have same value for value Now, Write function to Encode graph to list of integers given the root node .
Decode list of integers back to graph and return the root node. List encode(Node root); Node decode(List encodedList>);

I was able to provide solution for both functions. It's been more than a month, I did not receive any feedback, I mailed the recruiter multiple times but no answers. Any suggestions what can be done now?