Optimized Battery Charging is disabled - MBP still not charging

I often have the situation that my regular charging/discharging schedule is disrupted because of irregular office times and/or increased mobility.

So it often happens that, when I plug it in to work at a desk, the battery is way below 20%, but Big Sur still will not start charging it despite me turning off the "Optimized Battery Charging" option in system preferences.

Is this a software error or am I missing another option somewhere? I can't wait for it to decide to start charging 4 hours later, because I could be on the move again in 1 hour. It's frustrating to have had the MacBook plugged in and not have it charged at all this whole time.

Thanks for any help!