diff --git a/src/core/io/encoder.ts b/src/core/io/encoder.ts
index 7878eee8..94d5d059 100644
--- a/src/core/io/encoder.ts
+++ b/src/core/io/encoder.ts
@@ -568,7 +568,7 @@ function tagValuesToTokens(tagValues: TagValue[]): unknown[] {
     tokens.push(orderId);
 
     if (this.serverVersion >= MIN_SERVER_VER.MANUAL_ORDER_TIME)
-      tokens.push(orderCancel.manualOrderCancelTime ?? "");
+      tokens.push(orderCancel.manualOrderCancelTime);
 
     if (
       this.serverVersion >= MIN_SERVER_VER.RFQ_FIELDS &&
@@ -580,7 +580,7 @@ function tagValuesToTokens(tagValues: TagValue[]): unknown[] {
     }
 
     if (this.serverVersion >= MIN_SERVER_VER.CME_TAGGING_FIELDS) {
-      tokens.push(orderCancel.extOperator ?? "");
+      tokens.push(orderCancel.extOperator);
       tokens.push(orderCancel.manualOrderIndicator ?? Integer_MAX_VALUE);
     }
 
@@ -2251,7 +2251,7 @@ function tagValuesToTokens(tagValues: TagValue[]): unknown[] {
     }
 
     if (this.serverVersion >= MIN_SERVER_VER.CME_TAGGING_FIELDS) {
-      tokens.push(orderCancel.extOperator ?? "");
+      tokens.push(orderCancel.extOperator);
       tokens.push(orderCancel.manualOrderIndicator ?? Integer_MAX_VALUE);
     }