The irritation about the "repeated" deduction of payments is a common misunderstanding. The items listed in the payout notification under "Deduction of advance payments already made" are remunerations that you have already received, see the respective document date mentioned.

Payout notices always contain a kind of "payout history". They show an updated status for each payout. Displayed above in the disbursement documents are your current total claims for the respective distribution years. Since the GVL pays out the corresponding funds in several steps (until the final distribution), the amounts that have already been distributed are listed below and deducted accordingly from the total entitlements. What remains is the current remuneration entitlement that is paid out at the time of the respective distribution.

Until the final distribution of a given year, when your entitlement is ultimately determined, the previous payment history is therefore always documented, including the advances made. This does not mean that these funds will be deducted again from a new amount.