CFD tax advice Germany

Dear Has anyone done taxes on CFDs profit loss in Germany? I did recently and they took all the profits from the account (no. 1) and asked for taxes. Eg profit of 15,000, @ 25 % =3750 euro.

In a second account, I had a loss of 20,000 and the tax office is not taking into account.

Any German side trader/investor who had dealt with German taxes on CFD gain and loss.

Any reference to a tax consultant or personal experience will be much appreciated.

Thank you very much.

Best regards,