IMO all good. On my Samsungs charging stops entirely when reaching 85%. Then, it may go down a few %'s before it resumes with a trickle for a short time until 85% and stops charging.
So it’s all the best for the battery, experiencing zero heat on either phone or charger even when connected to charger 24\7 for long periods of wifi hotspot.
1st Android was a Samsung, a humble J, behaved perfect until resale.
2nd was Samsung, perfect until resale.
3rd was Samsung, perfect until resale.
Then tried Huawei & Motorola for a while, could have lived ok with those. But soon back to Samsung, cause: oneui, several of the excellent Samsung apps (Notes, Gallery, Camera pro mode, Smart Switch among others), great personalisation possibilities.
4th was Samsung, perfect until resale.
Current 5th & 6th, still perfect.