It is not possible to configure any SSCUIs, the Display -> Change option is disabled:
SAP S/4HANA Cloud.
If activation/scoping is in progress, the apps will open in display mode only.
It is necessary to wait the activation/scoping to be finished.
SSCUIs, Self-Service-Configurations-UI, edit mode. , KBA , SV-CLD-SSC , Self-Service-Configurations-UI , How To