Step count from activity not added to daily total

After a running activity, I checked my total steps for the day and noticed that there was zero increase. I checked my step history graph on the watch and noticed that the graph went up during my run to around 19k steps, then immediately back down to the amount. On the Connect app, the graph clearly shows that I reached around 20k steps, but the daily total was still around 10k, or what it was before my run. Is there any possible reason for this or is it a bug? It has never happened on my old Garmin devices