Run a New Best badge was not acquired when new personal record was achieved

Did you accept the record also at Personal Records | Garmin Connect or only on the watch? Is it listed as a PR in GC?

Yes, accepted in Garmin Connect on my phone.I have badge in my challenge list.

You can try:

• Waiting a few hours more
• Editing and saving the concerned activity
• Leaving and re-joining the Challenge
• Removing and manually re-assigning the PR
• Contacting the Support

I have the same issue with this badge. I received a notification both on the phone and on the web page that I received the badge. But then I actually didn't get it. There's a bug somewhere with this badge.

Personally, I got it instantly after achieving the record and saving the activity, even before approving the PR.

Lucky man :-)

I will try to ask Garmin helpdesk if they can help.

Or just do another record

Maybe. I have my record as a part of 5 KM run achievement