Bug Fixing - Integrating SSO with Google + Basic Authentication in Spring Boot

We have a web application project that needs to add additional functionalities which is to be able to Sign in With Google account. We have a bug in our SSO Server project that is unable to create a Security Context when a user is Signing in using Google account because it is unable to create Security Context via remote authentication process from other service. We will provide the mockup projects (4 projects) that heavily derivied from our original source codes. The mechanisms are as follows: 1. A potential user will need to sign up either by Sign up with google or manually entering their email address and will be validated later along with a phone number that will be validated via SMS 2. The difference is, when a user sign up with google account, the email does not need to be verified as the email will be valid anyway. 3. IF any users are registering the account using Google account. They can either use manual sign in (using username and password) OR Sign in with Google. The problem: To oversimplify the problem, let's pretend that we only have 3 projects (applications) A : SSO/ Login Page B : Home (Landing page) C : User account page 1. IF the user choose to "sign in with google" in A (SSO/Login Page), the user will be redirected to C (User account page) and it is success. I do this by creating a method of postForMap to invoke "/oauth/authorize" in A pretending to "authenticate" and check whether the user (email address) has been registered or not. If the account is existed then, I will create a Security Context for C while "hoping" that A will create a Security Context in it. 2. HOWEVER, when the user navigates to B (Home), B will try to check whether the token is valid and so on in A, and A does not recognise that the user has been logged in. I have checked in the database (table oauth_access_token) that verified that previous process of loadAuthentication has been successfully created by the SSO Server (A) 3. After countless hours of debugging, I have noticed that A (SSO Server) is failed to create a security context via remote authentication as aforementioned in number 1. We will provide a very detail information needed in order to successfully complete the project. The source codes to work and a complete technical documentation will be shared after a candidate is selected. Your task is only ONE which is to fix the bug and nothing more.