Why is this an issue?

To avoid confusion, even in different scopes, there should not be multiple modules with the same name.

How to fix it

Code examples

Noncompliant code example

File 1:
module fly;
  ...
endmodule

File 2:
module dream;
  module fly;
    ...
  endmodule
  ...
endmodule

Compliant solution

File 1:
module fly;
  ...
endmodule

File 2:
module dream;
  module sleep;
    ...
  endmodule
  ...
endmodule