diff --git a/src/core_modules/capture-core/converters/formToClient.js b/src/core_modules/capture-core/converters/formToClient.js
index 1e8a933f36..adca6b5b72 100644
--- a/src/core_modules/capture-core/converters/formToClient.js
+++ b/src/core_modules/capture-core/converters/formToClient.js
@@ -14,16 +14,20 @@ type RangeValue = {
     to: string,
 }
 
-function convertDateTime(formValue: DateTimeValue): string {
+function convertDateTime(formValue: DateTimeValue): ?string {
     const editedDate = formValue.date;
     const editedTime = formValue.time;
 
-    const momentTime = parseTime(editedTime).momentTime;
+    const parsedTime = parseTime(editedTime);
+    if (!parsedTime.isValid) return null;
+    const momentTime = parsedTime.momentTime;
     const hours = momentTime.hour();
     const minutes = momentTime.minute();
 
+    const parsedDate = parseDate(editedDate);
+    if (!parsedDate.isValid) return null;
     // $FlowFixMe[incompatible-type] automated comment
-    const momentDateTime: moment$Moment = parseDate(editedDate).momentDate;
+    const momentDateTime: moment$Moment = parsedDate.momentDate;
     momentDateTime.hour(hours);
     momentDateTime.minute(minutes);
     return momentDateTime.toISOString();
@@ -36,7 +40,9 @@ function convertDate(dateValue: string) {
 }
 
 function convertTime(timeValue: string) {
-    const momentTime = parseTime(timeValue).momentTime;
+    const parsedTime = parseTime(timeValue);
+    if (!parsedTime.isValid) return null;
+    const momentTime = parsedTime.momentTime;
     momentTime.locale('en');
     return momentTime.format('HH:mm');
 }