HI @Volker
Welcome to the eazyBI community and thanks for the greetings from Germany, they reached us in Latvia!
Dates in the Time dimension are collected during data import based on the issues information, thus, only dates with some activity (created, planned, resolved issues, status transitions, etc.) are included in the Time dimension.
For missing time periods, we suggest adding time members to the Time dimension manually as described here: Create reports - eazyBI for Jira
You may add the whole year 2023.
On the other hand, if you have only “Open issues” in the report (this measure shows the same value for all the future periods), you may add Time dimension also in Pages and select, for instance, default calculated Time member “Last 12 months” to limit the report time period.