You have enabled freesync,
freesync is not a static thing, instead it has three tiers, depending on your monitor:
Freesync (also reffered as adaptive sync) is the most basic anti-flicker
Freesync Premium is anti-flicker plus VRR (works well on low fps)
Freesync Premium Pro is anti-flicker, VRR, and can enable hdr at the same time
G-sync is used on monitors as marketing, if it says "compatible" then it means that this monitor has some freesync functionality. I had a look through your monitor user guide and as far as i can see only adaptive sync is supported.