Falling on exception Command failed with error 18 (AuthenticationFailed) when trying to use some api

i'm trying to create a simple java application with mongodb i'm trying to do it with docker but it's not working i`m create a yaml file docker-compose :

 version: "3.8"
 services:
   mongodb:
   image: mongo
   container_name: mongodb
ports:
  - 27017:27017
volumes:
  - data:/data
environment:
    - MONGO_INITDB_ROOT_USERNAME=rootuser
    - MONGO_INITDB_ROOT_PASSWORD=rootpass
mongo-express:
image: mongo-express
container_name: mongo-express
restart: always
ports:
  - 8081:8081
environment:
  - ME_CONFIG_MONGODB_ADMINUSERNAME=rootuser
  - ME_CONFIG_MONGODB_ADMINPASSWORD=rootpass
  - ME_CONFIG_MONGODB_SERVER=mongodb
volumes:
data: {}

networks:
default:
    name: mongodb_network

and in the properties file :

 spring.data.mongodb.authentication-database=admin
 spring.data.mongodb.username=rootuser
 spring.data.mongodb.password=rootpass
 spring.data.mongodb.database=demo
 spring.data.mongodb.port=27017
 spring.data.mongodb.host=localhost

but when i try to use some api this exeption is Thrown away :

 2022-01-30 19:22:15.309 ERROR 27632 --- [nio-8080-exec-1] o.a.c.c.C.[.[.[/]. 
 [dispatcherServlet]    : Servlet.service() for servlet [dispatcherServlet] in context with 
 path [] threw exception [Request processing failed; nested exception is 
 org.springframework.data.mongodb.UncategorizedMongoDbException: Exception authenticating 
 MongoCredential{mechanism=SCRAM-SHA-1, userName='rootuser', source='admin', password= 
 <hidden>, mechanismProperties=<hidden>}; nested exception is 
 com.mongodb.MongoSecurityException: Exception authenticating MongoCredential{mechanism=SCRAM- 
 SHA-1, userName='rootuser', source='admin', password=<hidden>, mechanismProperties=<hidden>}] 
 with root cause

 com.mongodb.MongoCommandException: Command failed with error 18 (AuthenticationFailed): 
 'Authentication failed.' on server localhost:27017. The full response is {"ok": 0.0, 
 "errmsg": "Authentication failed.", "code": 18, "codeName": "AuthenticationFailed"}

please can someone help me understand why it's happening