@DonkeyInvestor The back tax payment was because I had a tax-free bonus payment from my old employer and at the same time I also closed an old pension account. The two together led to this. I knew about the pension thing. I didn't know about the bonus payment. That caught me off guard 😅
And the advance payment was because the tax office thought (it's apparently automated) that I would always have such a high back payment now and therefore wanted a higher advance payment as a precaution.
