why Job Scheduler works fine just for first time?

Question

I'm implementing an SDK and I want to schedule a job that logs a message every 15 min(in the background). It works properly for the first 15 min but after that, it logs about every minute. this is my code below

class UploadJobService : JobService() {
companion object {
    private const val TAG = "TAG"
}

override fun onStartJob(params: JobParameters): Boolean {
    Log.d(TAG, "Job started")
    doBackgroundWork()
    return true
}

override fun onStopJob(params: JobParameters): Boolean {
    Log.d(TAG, "Job cancelled before completion")
    return true
}

 private fun doBackgroundWork(params: JobParameters?){
   job = CoroutineScope(Dispatchers.IO).launch {
       delay(2000)
       Log.d(TAG, "doBackgroundWork: Upload your file")
       jobFinished(params, true)
    }
   }
 }

and also

class UploadFilePeriodic {

companion object {
    val TAG = "TAG"
    private const val JOB_ID = 123

    fun scheduleJob(context: Context) {
        val info = JobInfo.Builder(JOB_ID, ComponentName(context, UploadJobService::class.java))
            .setPeriodic(15 * 60 * 1000)
            .setPersisted(true)
            .setRequiredNetworkType(JobInfo.NETWORK_TYPE_UNMETERED)
            .build()


        val scheduler = context.getSystemService(JOB_SCHEDULER_SERVICE) as JobScheduler
        val resultCode = scheduler.schedule(info)
        if (resultCode == JobScheduler.RESULT_SUCCESS) {
            Log.d(TAG, "Job scheduled")
        } else {
            Log.d(TAG, "Job scheduling failed")
        }
    }

    fun cancelJob(context: Context) {
        val scheduler = context.getSystemService(JOB_SCHEDULER_SERVICE) as JobScheduler?
        scheduler!!.cancel(JOB_ID)
        Log.d(TAG, "Job cancelled")
     }

  }

}

Also, did I use the coroutine correctly? Could anyone help me to fix it please?