ProRetention Angular Developer interview questions

First round is written test..I went for angular2+ interview but the written test questions were from AngularJS. After completing the written test the second round is face to face interview. In face to face interview the interviewer asked basic questions from angular and JavaScript.i answered this questions .I got positive review from the interviewer.he told me u will meet HR in next round. Then I was waiting for the HR round.then a person came to me and told , sorry u can leave today , u r not selected..I don't know the reason why they rejected me.