workmanager periodic request not working without setting a flex period

I have a unique periodic reques that runs without error when i set a flex period.

PeriodicWorkRequest workRequest = new PeriodicWorkRequest.Builder(EarthquakeUpdateWorker.class, 15, TimeUnit.MINUTES, 2, TimeUnit.MINUTES).setBackoffCriteria(BackoffPolicy.LINEAR, 2, TimeUnit.MINUTES).addTag(PERIODIC_WORK_KEY).setConstraints(constraints).build();
            WorkManager workManager = WorkManager.getInstance(context);
            workManager.enqueueUniquePeriodicWork(PERIODIC_WORK_KEY, ExistingPeriodicWorkPolicy.REPLACE, workRequest);

However if i remove the flex period eg.

PeriodicWorkRequest workRequest = new PeriodicWorkRequest.Builder(EarthquakeUpdateWorker.class, 15, TimeUnit.MINUTES).setBackoffCriteria(BackoffPolicy.LINEAR, 2, TimeUnit.MINUTES).addTag(PERIODIC_WORK_KEY).setConstraints(constraints).build();
            WorkManager workManager = WorkManager.getInstance(context);
            workManager.enqueueUniquePeriodicWork(PERIODIC_WORK_KEY, ExistingPeriodicWorkPolicy.REPLACE, workRequest);

I get an error like this

Didn't find WorkSpec for id 475c853c-09b8-4d38-9074-0b373f60c1b7

Any ideas on how to fix this or what is going on ?