diff --git a/mediator/src/utils/openmrs_sync.ts b/mediator/src/utils/openmrs_sync.ts
index 38283285..2b78aad3 100644
--- a/mediator/src/utils/openmrs_sync.ts
+++ b/mediator/src/utils/openmrs_sync.ts
@@ -84,13 +84,16 @@ export async function compare(
   const fhirIds = new Map(comparison.fhirResources.map(resource => [getKey(resource), resource]));
 
   function isValidDate(resource: fhir4.Resource) {
-    // if lastUpdated is not valid, cannot proceed, throw an error
-    const lastUpdated = new Date(resource.meta?.lastUpdated!);
+    // if lastUpdated is missing or invalid, cannot proceed, throw an error
+    if (!resource.meta?.lastUpdated) {
+      throw new Error("Last updated missing");
+    }
+    const lastUpdated = new Date(resource.meta.lastUpdated);
     if (isNaN(lastUpdated.getTime()) || isNaN(startTime.getTime())) {
       throw new Error("Invalid date format");
     }
 
-    // dont sync resources created with 2 * SYNC_INTERVAL of start time
+    // don't sync resources created with 2 * SYNC_INTERVAL of start time
     const syncWindow = (Number(SYNC_INTERVAL) * 1000) * 2
     const diff = lastUpdated.getTime() - startTime.getTime();
     return diff > syncWindow;
@@ -99,13 +102,10 @@ export async function compare(
   comparison.openMRSResources.forEach((openMRSResource) => {
     const key = getKey(openMRSResource);
     if (fhirIds.has(key)) {
-      // ok so the fhir server already has it
       results.toupdate.push(openMRSResource);
       fhirIds.delete(key);
-    } else {
-      if (isValidDate(openMRSResource)){
-        results.incoming.push(openMRSResource);
-      }
+    } else if (isValidDate(openMRSResource)){
+      results.incoming.push(openMRSResource);
     }
   });