using spring-security-oauth2-resource-server always invalid_token

[Markix]

I created a project as an Authorization Server using spring-security-oauth2. and create other project as an Resource Server using spring-security-oauth2-resource-server.
some config of Resource Server is that:

spring:
  security:
    oauth2:
      resourceserver:
        opaquetoken:
          client-id: client1
          client-secret: 123456
          introspection-uri: ${AuthorizationServerHost}/oauth/check_token

my operation:

1. login Authorization Server, get the token. e.g. IxPuO7hA9jVMWF08UI6HmDkizME=
2. access resource server api, but i always get the exception.
   org.springframework.security.authentication.AuthenticationServiceException: 400 : [{"error":"invalid_token","error_description":"Token was not recognised"}]

-- Debug
i found this call chain.

org.springframework.security.oauth2.server.resource.web.BearerTokenAuthenticationFilter#doFilterInternal
  org.springframework.security.oauth2.server.resource.web.DefaultBearerTokenResolver#resolve
    org.springframework.security.oauth2.server.resource.web.DefaultBearerTokenResolver#resolveFromAuthorizationHeader

The real token is IxPuO7hA9jVMWF08UI6HmDkizME=, but this code return IxPuO7hA9jVMWF08UI6HmDkizME .（‘=’ at the end is gone）
Caused /oauth/check_token always return invalid_token error.

-- Question
Is there a problem with the way I use it? or other? thx

---

dependency:

<dependency>
    <groupId>org.springframework.security.oauth.boot</groupId>
    <artifactId>spring-security-oauth2-autoconfigure</artifactId>
    <version>2.3.1.RELEASE</version>
</dependency>

<dependency>
    <groupId>org.springframework.security</groupId>
    <artifactId>spring-security-oauth2-resource-server</artifactId>
    <version>5.3.3.RELEASE</version>
</dependency>