Does not charge if processor load is high

Hi. I noticed that whenever a heavy computational load is on the processor (i.e. handbrake, or a game) the battery discharges and does not charge up again unless I stop/pause the process.
Using the mac normally the limit is in place (I set 80, charge to 83% but I don't mind) and works as expected.
MacBookPro15,3 i9@2,4Ghz 2019, Mojave.
Thanks