diff --git a/mcp-spring/mcp-spring-webflux/src/main/java/io/modelcontextprotocol/server/transport/WebFluxStreamableServerTransportProvider.java b/mcp-spring/mcp-spring-webflux/src/main/java/io/modelcontextprotocol/server/transport/WebFluxStreamableServerTransportProvider.java
index 144a3ce02..deebfc616 100644
--- a/mcp-spring/mcp-spring-webflux/src/main/java/io/modelcontextprotocol/server/transport/WebFluxStreamableServerTransportProvider.java
+++ b/mcp-spring/mcp-spring-webflux/src/main/java/io/modelcontextprotocol/server/transport/WebFluxStreamableServerTransportProvider.java
@@ -174,7 +174,7 @@ private Mono<ServerResponse> handleGet(ServerRequest request) {
 				return ServerResponse.badRequest().build();
 			}
 
-			if (!request.headers().asHttpHeaders().containsKey(HttpHeaders.MCP_SESSION_ID)) {
+			if (request.headers().header(HttpHeaders.MCP_SESSION_ID).isEmpty()) {
 				return ServerResponse.badRequest().build(); // TODO: say we need a session
 															// id
 			}
@@ -187,7 +187,7 @@ private Mono<ServerResponse> handleGet(ServerRequest request) {
 				return ServerResponse.notFound().build();
 			}
 
-			if (request.headers().asHttpHeaders().containsKey(HttpHeaders.LAST_EVENT_ID)) {
+			if (!request.headers().header(HttpHeaders.LAST_EVENT_ID).isEmpty()) {
 				String lastId = request.headers().asHttpHeaders().getFirst(HttpHeaders.LAST_EVENT_ID);
 				return ServerResponse.ok()
 					.contentType(MediaType.TEXT_EVENT_STREAM)
@@ -258,7 +258,7 @@ private Mono<ServerResponse> handlePost(ServerRequest request) {
 							.bodyValue(initResult));
 				}
 
-				if (!request.headers().asHttpHeaders().containsKey(HttpHeaders.MCP_SESSION_ID)) {
+				if (request.headers().header(HttpHeaders.MCP_SESSION_ID).isEmpty()) {
 					return ServerResponse.badRequest().bodyValue(new McpError("Session ID missing"));
 				}
 
@@ -313,7 +313,7 @@ private Mono<ServerResponse> handleDelete(ServerRequest request) {
 		McpTransportContext transportContext = this.contextExtractor.extract(request);
 
 		return Mono.defer(() -> {
-			if (!request.headers().asHttpHeaders().containsKey(HttpHeaders.MCP_SESSION_ID)) {
+			if (request.headers().header(HttpHeaders.MCP_SESSION_ID).isEmpty()) {
 				return ServerResponse.badRequest().build(); // TODO: say we need a session
 															// id
 			}
diff --git a/mcp-spring/mcp-spring-webmvc/src/main/java/io/modelcontextprotocol/server/transport/WebMvcStreamableServerTransportProvider.java b/mcp-spring/mcp-spring-webmvc/src/main/java/io/modelcontextprotocol/server/transport/WebMvcStreamableServerTransportProvider.java
index d85046a67..f2a58d4d8 100644
--- a/mcp-spring/mcp-spring-webmvc/src/main/java/io/modelcontextprotocol/server/transport/WebMvcStreamableServerTransportProvider.java
+++ b/mcp-spring/mcp-spring-webmvc/src/main/java/io/modelcontextprotocol/server/transport/WebMvcStreamableServerTransportProvider.java
@@ -240,7 +240,7 @@ private ServerResponse handleGet(ServerRequest request) {
 
 		McpTransportContext transportContext = this.contextExtractor.extract(request);
 
-		if (!request.headers().asHttpHeaders().containsKey(HttpHeaders.MCP_SESSION_ID)) {
+		if (request.headers().header(HttpHeaders.MCP_SESSION_ID).isEmpty()) {
 			return ServerResponse.badRequest().body("Session ID required in mcp-session-id header");
 		}
 
@@ -263,7 +263,7 @@ private ServerResponse handleGet(ServerRequest request) {
 						sessionId, sseBuilder);
 
 				// Check if this is a replay request
-				if (request.headers().asHttpHeaders().containsKey(HttpHeaders.LAST_EVENT_ID)) {
+				if (!request.headers().header(HttpHeaders.LAST_EVENT_ID).isEmpty()) {
 					String lastId = request.headers().asHttpHeaders().getFirst(HttpHeaders.LAST_EVENT_ID);
 
 					try {
@@ -354,7 +354,7 @@ private ServerResponse handlePost(ServerRequest request) {
 			}
 
 			// Handle other messages that require a session
-			if (!request.headers().asHttpHeaders().containsKey(HttpHeaders.MCP_SESSION_ID)) {
+			if (request.headers().header(HttpHeaders.MCP_SESSION_ID).isEmpty()) {
 				return ServerResponse.badRequest().body(new McpError("Session ID missing"));
 			}
 
@@ -433,7 +433,7 @@ private ServerResponse handleDelete(ServerRequest request) {
 
 		McpTransportContext transportContext = this.contextExtractor.extract(request);
 
-		if (!request.headers().asHttpHeaders().containsKey(HttpHeaders.MCP_SESSION_ID)) {
+		if (request.headers().header(HttpHeaders.MCP_SESSION_ID).isEmpty()) {
 			return ServerResponse.badRequest().body("Session ID required in mcp-session-id header");
 		}