How to have "Hello" appear at 2 frequencies using Adalm Pluto and GNURadio?

[Avana Tan]

Good day all.

Can anyone help me? I am facing the following problem:

This is my GNURadio grc schematic:

Upon running the above grc schematic, this GUI will pop up:

And this will appear at the bottom left of the grc schematic: 

The problem I am facing:

When I manually change the Carrier Frequency (MHz) from 700.0m to 900.0m (in red circle below) and the Symbol Rate (Symbols per second) from 160k to 100k (in green circle below), 

This (below picture) should continue running:  

 

Can anyone help me with the GNURadio grc schematic please?

Appreciate all help and input.

Thank you.

~Talia