I had similar problem with my offset. I have edited a bit my blendspace idle animations and it triggered this problem. Open you anim blueprint and disconnect parts to identify where your problem is. I had mine with offset. Once i disconnected it it worked fine. Later i found out i edited animations in my blendspace but i used original animation as aditive to my offset blend space and it caused this issue. These two animations was coliding. So i used the new idle animation i edited to create new offset animations with this new anim as aditive and it works fine.