In this video you are copying over the existing data with the same value (-1.3/2) on each keyframe.
What you should be doing is subtracting this from the current value that is already in there.
But also the 1.3 value is the full length of the stride in MY walkcycle. YOUR walkcycle could be a different length, so make sure you are using the correct value for your animation (it might be the same but just bringing that up in case it’s not the same as mine)
