I have also tried thicker pads in various boots, and inevitably they made the boot not fit right and didn't work.

For quite some time now I have been using his Cloud boots with the Soft Ride inserts. If you order the inserts in narrow, they have an edge on the sides that helps to hold the boot more securely in place. The Soft Rides fall off no matter what I do.
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Deb and Scotty I/R Probably PPID
Northwest Illinois, May 13, 2019
Case History:
 https://ecir.groups.io/g/CaseHistory/files/Deb%20and%20Scotty
Photos:
https://ecir.groups.io/g/CaseHistory/album?id=90619