Timer time Invalid format

I created BPMN, when the user enter the data, the validation should be trigered only at 15:00. So i have a timer and i configured it with a fix time.

With this config i have this error in my project:

TASK/CLIENT-01009 Exception while completing the external task: The corresponding process instance could not be resumed. Reason: status code: 500, reason phrase: {“type”:“ProcessEngineException”,“message”:"ENGINE-09027 Exception while resolving duedate ‘15:10:00’: Invalid format: “15:10:00” is malformed at “:10:00"”}

@Aymen_Kanzari Timers are configured using an ISO 8601 time format. A timer definition must have exactly one of the following elements.