EDIT: I uploaded a newer file for the block clip that better fits the groove wheel of the filament feeder. Also, this one spans across the backside keeping it from being able to move or rotate in any manner around the groove wheel keeping it in place very nicely. It does not impede the turning of the groove wheel at all so no binding or resistance is present. The flat side of the clip goes toward the exit side of the filament guide.

This simple clip solved my problems using TPU with my ANET E10 3D printer. By putting this clip around the backside of the roller bearing on the feed motor guide, the TPU was not allowed to deviate as it passed through the infeed through to the bowden tube. Even though the ANET E10 comes with a decently designed aluminum filament feeder that has the distance across the open area where the filament feeds mostly closed off, it just wasn't enough to keep the TPU from ocassionally kinking and trying to push past the groove of the guide roller and would cause a jam. With this clip and the correct feed settings for the type of TPU you have, you can probably eliminate those issues. I have successfully printed a LOT of TPU pieces now without issue. I have tried both PolyFlex (using 30mm/s in Cura) with no issues and YOYI TPU (15mm/s in Cura) with great success.

NOTE: You may need to remove the grooved wheel to get the clip to snap on, then place it back onto the base. The grooved wheel should turn freely in the clip.

This thing was made with Tinkercad. Edit it online https://www.tinkercad.com/things/boLffqAYEmr