Bleeding walnuts advice re grafting

I have 10 walnuts regia growing in pots that I have grafted.

6 are seemily doing fine, the other 4 are bleeding badly.

they are grown in pots and have been equally dried off.

The 4 bleeders, I have removed the scions, dried them with a towel and stored them. The rootstocks however even after 2 days are still continuing to bleed.

Any advice on what I can? Is it just sit and wait and do not water?