With the cyclic F-modifier, my character walks ahead but the arms stay back

My character does 2 walk cycles nicely (80 frames) in the y-direction.
I then wanted it to continue walking indefinitely and enabled the Cycles F-modifier in the Graph Editor for 3 controllers - feet and hips.
The character feet now continues walking nicely but after 80 frames the arms refuse to swing in tune with the legs and stay back fixed to the body. (Applying the modifier to the hands controllers makes no difference)
I am baffled why this is happening. In the F-modifier panel, I had set NO in the ‘Before’ section and ‘repeat with Offset’ in the ‘After’.

I’d really appreciate some suggestion or tip.