diff --git a/CHANGELOG.md b/CHANGELOG.md
index 300ed72f1..f1673adac 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -18,6 +18,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - program: add add update_liquidation_margin_buffer_ratio ([#695](https://github.com/drift-labs/protocol-v2/pull/695))
 - program: account for fee pool when settling positive pnl ([#687](https://github.com/drift-labs/protocol-v2/pull/687))
 - sdk: fix bug which incorrectly calculated leverage after trade for a market with no position but short orders open
+- sdk: fix bug in modifying an order that previously had auction params to a non-auction order
 
 ### Breaking
 
diff --git a/sdk/src/driftClient.ts b/sdk/src/driftClient.ts
index 60a10b685..b3443d47c 100644
--- a/sdk/src/driftClient.ts
+++ b/sdk/src/driftClient.ts
@@ -4649,12 +4649,12 @@ export class DriftClient {
 			oraclePriceOffset: newOraclePriceOffset || null,
 			triggerPrice: newTriggerPrice || null,
 			triggerCondition: newTriggerCondition || null,
-			auctionDuration: auctionDuration || null,
-			auctionStartPrice: auctionStartPrice || null,
-			auctionEndPrice: auctionEndPrice || null,
-			reduceOnly: reduceOnly || null,
+			auctionDuration: auctionDuration || 0,
+			auctionStartPrice: auctionStartPrice || ZERO,
+			auctionEndPrice: auctionEndPrice || ZERO,
+			reduceOnly: reduceOnly || false,
 			postOnly: postOnly || null,
-			immediateOrCancel: immediateOrCancel || null,
+			immediateOrCancel: immediateOrCancel || false,
 			policy: policy || null,
 			maxTs: maxTs || null,
 		};
@@ -4767,12 +4767,12 @@ export class DriftClient {
 			oraclePriceOffset: newOraclePriceOffset || null,
 			triggerPrice: newTriggerPrice || null,
 			triggerCondition: newTriggerCondition || null,
-			auctionDuration: auctionDuration || null,
-			auctionStartPrice: auctionStartPrice || null,
-			auctionEndPrice: auctionEndPrice || null,
-			reduceOnly: reduceOnly || null,
+			auctionDuration: auctionDuration || 0,
+			auctionStartPrice: auctionStartPrice || ZERO,
+			auctionEndPrice: auctionEndPrice || ZERO,
+			reduceOnly: reduceOnly || false,
 			postOnly: postOnly || null,
-			immediateOrCancel: immediateOrCancel || null,
+			immediateOrCancel: immediateOrCancel || false,
 			policy: policy || null,
 			maxTs: maxTs || null,
 		};