I am getting the same battery health here. Did you return your phone? is this some first round phone problem?
I considered it many times, but never got around to it because I couldn't be bothered to backup and wipe everything and set it all up from scratch on my old phone. But the warranty claim would probably have been rejected anyway, because I think my poor battery health was due to AccuBattery getting confused by Samsung's 85% charge limit.
I charged my phone to 100% once upon receiving it and enabled the 85% limit feature immediately afterwards. Since then, my battery capacity has been dropping a few mAh every week according to AccuBattery, however a few days ago I decided to try disabling the 85% limit and charge the phone from 40% to 100%.
After that, my battery health in AccuBattery suddenly jumped from 3199 mAh to 3225 mAh (based on 36 sessions with 36813 mAh charged in total). When looking at the battery capacity graph, I can see that the battery capacity was estimated to >3600 mAh during that specific charging session, which is a new record:
So... I don't think AccuBattery's health predictions can be trusted when the phone doesn't charge beyond 85% - it seems as if 0-85% is considered 0-100% from AccuBattery's point of view when the Samsung charge limiter is in effect.
I have been very happy with AccuBattery in the past, but now I regret that I ever installed it on this phone because it has caused me nothing but worries.