Resigned on day 1 but employer asking for settlement

Hi, Please suggest me for this situation. I have joined one IT company and resigned on Day 1 by sending resignation email from my personal email. After 15 days, I have joined another company. Now, the previous company is asking settlement amount. The bigger problem is, they have credited amount to my PF account without credited any salary to my Bank account. Earlier, I have sent email to previous employer to not create or credit any PF account/amount as I am not going to continue with this job. Which causing issue for my current employer to credit PF amount to existing UAN account. My question, is it valid for them to hold my PF account or asking for money? Is it possible if I request them to give my last working day of 7 or 10 days(so that it won't overlap with my present employer joining date) after clear the settlement amount. Could you please suggest me on this? What is the solution to release the PF account so that my current employer can credit his PF amount. Thanks, Tanmoy.