Downtime don't disappear

Hello again,
I have problems with downtimes. I’m trying to set up a daily downtime for a service. I can only completely remove the host from the game. Then all services are blocked. If I delete this downtime again, it remains visible in Icingaweb. If i enter

“icinga2 object list --type ScheduledDowntime”

shows no downtime. Is the database entry not updated via icingaweb?
Now i have for each service 2 entrys in icingaweb one fixed Downtime and one flexible Downtime. How can I solve this Problem?
Bildschirmfoto vom 2022-09-29 12-42-19

here my tried entry:

apply ScheduledDowntime "load4backup" to Service {
   comment = "Daily Overload"
   fixed = true
   ranges = {
        monday = "00:30-06:00"
        tuesday = "00:30-06:00"
        wednesday = "00:30-06:00"
        thursday = "00:30-06:00"
        friday = "00:30-06:00"
        saturday = "00:30-06:00"
        sunday = "00:30-06:00"
assign where ( == "esn-svh001" && == "Load" )

My Enviroment:
icinga2 - The Icinga 2 network monitoring daemon (version: r2.13.5-1)
System information:
Platform: Ubuntu
Platform version: 20.04.5 LTS (Focal Fossa)
Kernel: Linux
Kernel version: 5.13.0-30-generic