Move from Germany to UK - Foreign Tax Credit Relief

Hi, Last year I moved from Germany to UK. I had 3 months worth of German employment until July 2022, then transferred to UK and started employment. I paid all taxes required in Germany. Because of Covid my family continued to live in UK and in the end our move to Germany did not complete and I returned to UK after 3 years in Germany. For my UK tax return because I had significant ties in UK I had to include my German income for 2022-2023 UK tax return. My issue is that my accountant informs me that not all of the taxes I had deducted at source in Germany can be used as Foreign Tax Credit Relief. The taxes I paid that I cannot use are Statutory Pension Contribution 9.3% . Statutory National Health Insurance 7.3%. Statutory Long Term Care 1.7% and Unemployment Insurance 1.3%. These were all deducted at source and I cannot claim a refund back for this. I would think that these along with German Income tax and Solidarity tax should be included for Foreign Tax Credit Relief. I cannot find documentation that they are not included. My accountant tells me I cannot include them and now I face a huge extra tax bill in UK for the German income. This seems very unfair and not the point of the double taxation agreement. This should be to avoid double taxation which it seems that I am now having to do. Please could I have confirmation that these additional taxes are either included or not. And if they are not included then I feel that should be. Thank you, Dane Anglia Viking

Hi Jakob Andreasen,
Only Income Tax paid in Germany on your employment income, can be claimed as a Foreign Tax Credit.
You cannot claim for any of the others mentioned, as they are not Income Taxes and not covered by the double taxation agreement.
Thank you.