I signed a bond with my previous employer when I joined. I had issues with my previous employer regarding working shifts, salary increments, and transfers. I got a better opportunity after working in the previous organization. However, while quitting the job, I didn't submit any resignation letter. After two months, they sent me a recovery letter, and now, after one year, they have sent me a bond repayment letter. Is this letter valid since they sent me a recovery letter before sending the bond repayment letter?