@DH-Sf
The most likely reason for not receiving a password reset email is that you are inadvertently trying to use an email address different from the one you previously had been using to log onto the Google Nest app.
If that is NOT the case, you could try contacting Support to see if something is going on with password reset emails:
1. Go to https://support.google.com/googlenest/gethelp.
2. Select a category/product family, and type in a brief description of the issue, then click "Next".
3. Click "Other", then click "Next step".
4. Under "Resources", just click "Next step". (Clicking one of the listed links will bring up a Help page page.)
5. Under "Contact options", choose to get a phone call or chat with the team, depending on availability in your country.
