If you have water filling into the brine tank during the brine draw phase, there may be some issues with how the water drains from the system.
First, stop the regeneration by pressing the UP and DOWN arrows together at the same time.
Your screen will show ‘goto sr’ for a few minutes, then take you back to the main screen.
Next, manually remove any extra water and bring the brine tank level to half a tank full of water.
Next, follow the instructions for checking a potential back pressure issue here.