Dell E525W - Message 016-370

Hello,
I have a Dell E525W printer (from 2015) and since yesterday it shows the Message 016-370. I restarted it severeal times and I also tried to reset the NVM. But when I chose Reset System NVM it hangs for hours. After restaring the display is shows only "ready to copy" Trying then to copy it says in the display "Cannot execute this operation"

I am not able to update the Firmware. I the status via USB it says "not ready" and abort the installation with the message" Check the printer is ready".  When trying the Update via network the printer is found but with the status "not complete" too and at the end it says "unable to download data to the printer".

Can anybody help?

Thanks