NextCloudPi - Update not possible

Hello,

I am using Nextcloud on a Raspberry Pi 3a with NextcloudPi.
In the command line the message for an update is displayed: “NextcloudPi v1.53.1 is outdated”
If I try to update to the current version, this is aborted with an error:
ncp_error

Has always worked without problems so far.
I also tried it via ncp-config, but the same error.
Does anyone have an explanation and a solution?

Greetings, Michael