@Senthilnath TM Thanks for reporting this. This is known issue and feedback has been conveyed to product team. For now, I would suggest you use PowerShell command to create software update configuration.
Adding example from Microsoft docs for reference.
$startTime = [DateTimeOffset]"2023-03-13T21:00"
$targetMachines = @(
"/subscriptions/22e2445a-0984-4fa5-86a4-0280d76c4b2c/resourceGroups/compute/providers/Microsoft.Compute/virtualMachines/vm-w-01",
"/subscriptions/22e2445a-0984-4fa5-86a4-0280d76c4b2c/resourceGroups/compute/providers/Microsoft.Compute/virtualMachines/vm-w-02"
)
$duration = New-TimeSpan -Hours 2
$schedule = New-AzAutomationSchedule -ResourceGroupName "mygroup" `
-AutomationAccountName "myaccount" `
-Name MyWeeklySchedule `
-StartTime $startTime `
-DaysOfWeek Saturday `
-WeekInterval 1 `
-ForUpdateConfiguration
New-AzAutomationSoftwareUpdateConfiguration -ResourceGroupName "mygroup" `
-AutomationAccountName "myaccount" `
-Schedule $schedule `
-Windows `
-AzureVMResourceId $targetMachines `
-IncludedUpdateClassification Critical `
-Duration $duration
UpdateConfiguration : Microsoft.Azure.Commands.Automation.Model.UpdateManagement.UpdateConfiguration
ScheduleConfiguration : Microsoft.Azure.Commands.Automation.Model.Schedule
ProvisioningState : Provisioning
ErrorInfo :
ResourceGroupName : mygroup
AutomationAccountName : myaccount
Name : MyWeeklySchedule
CreationTime : 9/14/2018 3:53:27 AM +00:00
LastModifiedTime : 9/14/2018 3:53:27 AM +00:00
Description :