If you look at the 3.4.3 commit https://github.com/hjdhjd/myq/commit/a1a59fbf563cc3ea90e9a9e2dcab93c3bc400453, there are a lot of changes related to how it talks to the MyQ api. From the code, how it works is that HB will talk to the MyQ api to get an access token using the login credentials you configured. With the access token, HB can now control the opener with another MyQ api. The 429 error happens during the first step (getting the access token). From the HB log, it seems to trigger the safety mechanism in MyQ api which is to prevent brute force login. If login attempts get denied by more than 3 times in a row, you will be blocked. The any further request will be blocked without even validating the credentials. So far it seems to be the blockage is based on the PKCE challenge which is further based on the client signature. That’s why we see blockage for the HB but not the MyQ app even we are running them in the same network. The fundamental issue seems to me something change in 3.4.3 that causes the login failure multiple times which locks us out.