diff --git a/server/src/repositories/monitors/IMonitorsRepository.ts b/server/src/repositories/monitors/IMonitorsRepository.ts
index 88c039881..8c5f63e7d 100644
--- a/server/src/repositories/monitors/IMonitorsRepository.ts
+++ b/server/src/repositories/monitors/IMonitorsRepository.ts
@@ -41,7 +41,7 @@ export interface IMonitorsRepository {
 	findMonitorsSummaryByTeamId(teamId: string, config?: SummaryConfig): Promise<MonitorsSummary>;
 	findGroupsByTeamId(teamId: string): Promise<string[]>;
 	removeNotificationFromMonitors(notificationId: string): Promise<void>;
-	updateNotifications(monitorIds: string[], notificationIds: string[], action: "add" | "remove" | "set", teamId: string): Promise<number>;
+	updateNotifications(teamId: string, monitorIds: string[], notificationIds: string[], action: "add" | "remove" | "set"): Promise<number>;
 	deleteByTeamIdsNotIn(teamIds: string[]): Promise<number>;
 	findAllMonitorIds(): Promise<string[]>;
 }
diff --git a/server/src/repositories/monitors/MongoMonitorsRepository.ts b/server/src/repositories/monitors/MongoMonitorsRepository.ts
index 07f9ee7bb..93056c747 100644
--- a/server/src/repositories/monitors/MongoMonitorsRepository.ts
+++ b/server/src/repositories/monitors/MongoMonitorsRepository.ts
@@ -299,10 +299,10 @@ class MongoMonitorsRepository implements IMonitorsRepository {
 	};
 
 	updateNotifications = async (
+		teamId: string,
 		monitorIds: string[],
 		notificationIds: string[],
-		action: "add" | "remove" | "set",
-		teamId: string
+		action: "add" | "remove" | "set"
 	): Promise<number> => {
 		let objectIds;
 		let notificationObjectIds;
diff --git a/server/src/service/business/monitorService.ts b/server/src/service/business/monitorService.ts
index 6e0446645..ff7b87fe8 100644
--- a/server/src/service/business/monitorService.ts
+++ b/server/src/service/business/monitorService.ts
@@ -449,7 +449,7 @@ export class MonitorService implements IMonitorService {
 		notificationIds: string[];
 		action: "add" | "remove" | "set";
 	}): Promise<number> => {
-		const modifiedCount = await this.monitorsRepository.updateNotifications(monitorIds, notificationIds, action, teamId);
+		const modifiedCount = await this.monitorsRepository.updateNotifications(teamId, monitorIds, notificationIds, action);
 
 		// If notifications were updated, we should update the jobs in the queue
 		if (modifiedCount > 0) {
diff --git a/server/src/service/business/userService.ts b/server/src/service/business/userService.ts
index a4ef15cee..48ee5cfbf 100644
--- a/server/src/service/business/userService.ts
+++ b/server/src/service/business/userService.ts
@@ -166,7 +166,7 @@ export class UserService implements IUserService {
 			if (!html) {
 				throw new Error("Failed to build welcome email HTML");
 			}
-			this.emailService.sendEmail(newUser.email, "Welcome to Uptime Monitor", html as string).catch((error: unknown) => {
+			this.emailService.sendEmail(newUser.email, "Welcome to Uptime Monitor", html).catch((error: unknown) => {
 				this.logger.warn({
 					message: error instanceof Error ? error.message : "Unknown error",
 					service: SERVICE_NAME,
diff --git a/server/src/validation/notificationValidation.ts b/server/src/validation/notificationValidation.ts
index cf187f7b4..cc375ed2f 100644
--- a/server/src/validation/notificationValidation.ts
+++ b/server/src/validation/notificationValidation.ts
@@ -103,4 +103,10 @@ export const updateNotificationsValidation = z.object({
 	monitorIds: z.array(z.string()).min(1, "At least one monitor ID is required"),
 	notificationIds: z.array(z.string()),
 	action: z.enum(["add", "remove", "set"] as const),
+}).refine((data) => {
+	if (data.action !== "set" && data.notificationIds.length === 0) return false;
+	return true;
+}, {
+	message: "Notification IDs cannot be empty unless action is 'set'",
+	path: ["notificationIds"],
 });