When i reduced my oil to half way up the crosshatching, the warning came on twice after that. That was 18 months ago on a 6.1 2020 (Startline poverty edition!), no warnings since.
After an oil service, oil has been filled full again, I get home and take out about 4-500 ml through the dipstick tube with a £10 siphon kit from Karparts. I've asked my local VW indy to put 500ml less in during a service, but that seems to be beyond them!
How long ago did you reduce your oil?