I believe the speed limit is set in the motor controller and the display only shows it and/or allows updating it.

Can you please elaborate on what you mean by “in the DP C080.CB i configured”? Does the display have the option to increase the speed limit to 60km/h? Did you press “+” and “-” at the same time to save the setting? Does it show the 60km/h limit in the display after restarting the bike?

I personally don’t have experience with the motor you mentioned. Have you tried using the OpenBafangTool mentioned in the earlier comments?