diff --git a/alerting/src/main/kotlin/org/opensearch/alerting/transport/TransportIndexMonitorAction.kt b/alerting/src/main/kotlin/org/opensearch/alerting/transport/TransportIndexMonitorAction.kt
index 0546d0733..6c943cef8 100644
--- a/alerting/src/main/kotlin/org/opensearch/alerting/transport/TransportIndexMonitorAction.kt
+++ b/alerting/src/main/kotlin/org/opensearch/alerting/transport/TransportIndexMonitorAction.kt
@@ -9,10 +9,15 @@ import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.launch
 import org.apache.logging.log4j.LogManager
+import org.opensearch.OpenSearchException
 import org.opensearch.OpenSearchSecurityException
 import org.opensearch.OpenSearchStatusException
+import org.opensearch.ResourceAlreadyExistsException
 import org.opensearch.action.ActionListener
 import org.opensearch.action.ActionRequest
+import org.opensearch.action.admin.cluster.health.ClusterHealthAction
+import org.opensearch.action.admin.cluster.health.ClusterHealthRequest
+import org.opensearch.action.admin.cluster.health.ClusterHealthResponse
 import org.opensearch.action.admin.indices.create.CreateIndexResponse
 import org.opensearch.action.admin.indices.get.GetIndexRequest
 import org.opensearch.action.admin.indices.get.GetIndexResponse
@@ -297,10 +302,30 @@ class TransportIndexMonitorAction @Inject constructor(
             if (!scheduledJobIndices.scheduledJobIndexExists()) {
                 scheduledJobIndices.initScheduledJobIndex(object : ActionListener<CreateIndexResponse> {
                     override fun onResponse(response: CreateIndexResponse) {
-                        onCreateMappingsResponse(response)
+                        onCreateMappingsResponse(response.isAcknowledged)
                     }
                     override fun onFailure(t: Exception) {
-                        actionListener.onFailure(AlertingException.wrap(t))
+                        // https://github.com/opensearch-project/alerting/issues/646
+                        if (t is ResourceAlreadyExistsException && t.message?.contains("already exists") == true) {
+                            scope.launch {
+                                // Wait for the yellow status
+                                val request = ClusterHealthRequest()
+                                    .indices(SCHEDULED_JOBS_INDEX)
+                                    .waitForYellowStatus()
+                                val response: ClusterHealthResponse = client.suspendUntil {
+                                    execute(ClusterHealthAction.INSTANCE, request, it)
+                                }
+                                if (response.isTimedOut) {
+                                    actionListener.onFailure(
+                                        OpenSearchException("Cannot determine that the $SCHEDULED_JOBS_INDEX index is healthy")
+                                    )
+                                }
+                                // Retry mapping of monitor
+                                onCreateMappingsResponse(true)
+                            }
+                        } else {
+                            actionListener.onFailure(AlertingException.wrap(t))
+                        }
                     }
                 })
             } else if (!IndexUtils.scheduledJobIndexUpdated) {
@@ -346,6 +371,7 @@ class TransportIndexMonitorAction @Inject constructor(
                 val query = QueryBuilders.boolQuery().filter(QueryBuilders.termQuery("${Monitor.MONITOR_TYPE}.type", Monitor.MONITOR_TYPE))
                 val searchSource = SearchSourceBuilder().query(query).timeout(requestTimeout)
                 val searchRequest = SearchRequest(SCHEDULED_JOBS_INDEX).source(searchSource)
+
                 client.search(
                     searchRequest,
                     object : ActionListener<SearchResponse> {
@@ -401,8 +427,8 @@ class TransportIndexMonitorAction @Inject constructor(
             }
         }
 
-        private fun onCreateMappingsResponse(response: CreateIndexResponse) {
-            if (response.isAcknowledged) {
+        private fun onCreateMappingsResponse(isAcknowledged: Boolean) {
+            if (isAcknowledged) {
                 log.info("Created $SCHEDULED_JOBS_INDEX with mappings.")
                 prepareMonitorIndexing()
                 IndexUtils.scheduledJobIndexUpdated()