HTTP Header Insertion fails as Invalid Header - HTTP Error 400

The webpage fails on adding multiple Values as HTTP Header.

• PAN-OS 8.1 & above.
• Configuring multiple Values for HTTP Header Insertion.

• The issue was caused by adding multiple values for HTTP header separated by different line(s).

• The running config looked like the following

http-header-insertion {
                  test {
                    type {
                      "Microsoft Office365 Tenant Restrictions" {
                        domains [ login.microsoftonline.com login.windows.net login.microsoft.com];
                        headers {
                          header-0 {
                            header Restrict-Access-To-Tenants;
                            value testglobal.com           <<<<<<<<< 
testglobal.onmicrosoft.com;           <<<<<<<<< 
                            log yes;
                          }
                          header-1 {
                            header Restrict-Access-Context;
                            value 9asdf321-566c-4d0b-ac6b-01253eb2fcc1;
                            log yes;
                          }
                        }
                      }
                    }
                  }

• The multiple values for HTTP header must be separated by comma ','

• The running config looked like the following 

http-header-insertion {
                  test {
                    type {
                      "Microsoft Office365 Tenant Restrictions" {
                        domains [ login.microsoftonline.com login.windows.net login.microsoft.com];
                        headers {
                          header-0 {
                            header Restrict-Access-To-Tenants;
                            value testglobal.com,testglobal.onmicrosoft.com; <<<<<<<<<
                            log yes;
                          }
                          header-1 {
                            header Restrict-Access-Context;
                            value 9asdf321-566c-4d0b-ac6b-01253eb2fcc1;
                            log yes;
                          }
                        }
                      }
                    }
                  }

KB Article for configuration:

Sanctioned Access For Office365 Enterprise Using HTTP Header Insertion