In honesty, I don’t have too much experience with EndeavourOS yet so I’d wait for someone more experienced to answer but it may be a KDE Plasma 6 issue. Whilst it’s less buggy than the Plasma 5 release, many have been experiencing issues along the lines of this and it may be fixed down the line with an upstream update.
KDE Users Should've Waited - #8 by GolDNenex for more information
But regardless, I’d wait for a more experienced person to answer. But figured I should give a response regardless.