diff --git a/back/data/cron.ts b/back/data/cron.ts
index 7dc703f6..56f0ec81 100644
--- a/back/data/cron.ts
+++ b/back/data/cron.ts
@@ -50,7 +50,10 @@ export enum CrontabStatus {
 interface CronInstance extends Model<Crontab, Crontab>, Crontab {}
 export const CrontabModel = sequelize.define<CronInstance>('Crontab', {
   name: DataTypes.STRING,
-  command: DataTypes.STRING,
+  command: {
+    unique: 'command',
+    type: DataTypes.STRING,
+  },
   schedule: DataTypes.STRING,
   timestamp: DataTypes.STRING,
   saved: DataTypes.BOOLEAN,
diff --git a/back/services/cron.ts b/back/services/cron.ts
index 8b817505..ec671507 100644
--- a/back/services/cron.ts
+++ b/back/services/cron.ts
@@ -31,6 +31,12 @@ export default class CronService {
   }
 
   public async insert(payload: Crontab): Promise<Crontab> {
+    const cron = await CrontabModel.findOne({
+      where: { command: payload.command },
+    });
+    if (cron) {
+      return cron;
+    }
     return await CrontabModel.create(payload, { returning: true });
   }
 
diff --git a/back/services/env.ts b/back/services/env.ts
index 61331ebd..a82db1a1 100644
--- a/back/services/env.ts
+++ b/back/services/env.ts
@@ -108,15 +108,18 @@ export default class EnvService {
       };
     }
     try {
-      const result = await this.find(condition);
+      const result = await this.find(condition, [['position', 'DESC']]);
       return result as any;
     } catch (error) {
       throw error;
     }
   }
 
-  private async find(query: any, sort?: any): Promise<Env[]> {
-    const docs = await EnvModel.findAll({ where: { ...query } });
+  private async find(query: any, sort: any = []): Promise<Env[]> {
+    const docs = await EnvModel.findAll({
+      where: { ...query },
+      order: [...sort],
+    });
     return docs;
   }
 
diff --git a/back/services/open.ts b/back/services/open.ts
index ab044ec0..924b277a 100644
--- a/back/services/open.ts
+++ b/back/services/open.ts
@@ -12,14 +12,15 @@ export default class OpenService {
   constructor(@Inject('logger') private logger: winston.Logger) {}
 
   public async findTokenByValue(token: string): Promise<App | null> {
-    const doc = await this.getDb({
-      where: sequelize.fn(
+    const doc = await this.getDb(
+      sequelize.fn(
         'JSON_CONTAINS',
         sequelize.col('tokens'),
         JSON.stringify({ value: token }),
       ),
-    });
+    );
     return doc;
+    AppModel.upsert;
   }
 
   public async create(payload: App): Promise<App> {
@@ -50,7 +51,7 @@ export default class OpenService {
   }
 
   public async getDb(query: any): Promise<App> {
-    const doc: any = await AppModel.findOne({ where: { ...query } });
+    const doc: any = await AppModel.findOne({ where: query });
     return doc && (doc.get({ plain: true }) as App);
   }