Code 41026 repeat User?

[Soulmate]

Hi all
Iam based in Germany and was told to Install a DTU 666 of fox to cut Power Peaks to 60 %.
I was Not able to Start with my User Account,so i tried to create one as Installer ..got the Code 41026 repeat User...
What does that mean?
IS there any other Option to follow the Rules given by Provider ?
Thx
Mike

[Will]

Hello,

What inverter model please?

[Soulmate]

Hi

Its the TG 5 G 3
Best regards