I don't know the polo but if it's like other autos you open the drain hole on a warm engine w/engine running and see if fluid comes out. If not, it's not overfilled. If a few drops come out, it's OK. If nothing comes out, it could be low, add fluid until it drips slowly out. The fluid level goes up-down depending on temp so you have to refer to the owner's manual to see what temp the fluid should be. There is probably no dipstick.
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