CSRF throwing 403 only in cloud

Question

The Configuration for CSRF works locally just as it should, however once it is deployed in a Cloud System i get a 403 for the Post requests.

These are the essential changes in the GUI (VUE) i made:

let headers = {
    'Content-Type': 'application/json;charset=UTF-8'
    'Accept': 'application/json' 
    'Access-Control-Allow-Origin': SERVER_URL+'/*'
    "Authorization": "Bearer "+ keycloak.token 
    'Access-Control-Allow-Credentials': 'true'
};

const axiosInstance = axios.create({
    withCredentials: true,
    baseURL: SERVER_URL,
    headers: headers
});

axiosInstance.post('/postrequestname', data).then(
...

In my Backend (Spring Boot) i added the following in the SecurityConfig (Extended from KeycloakWebSecurityConfigurerAdapter):

httpSecurity.csrf().csrfTokenRepository(CookieCsrfTokenRepository.withHttpOnlyFalse());

And also added allowCredentials = "true" to the Rest Controllers.

My issue as said earlier is, that this works just fine in my local development, however once it is deployed it does throw a 403 Forbidden for some reason and i can not seem to find what the issue is.