As I explained earlier, this is not the expense that was borne by you, for which you are claiming reimbursement. It's an income for two months that you would have received from the previous employer if you had served the notice period. Please read the example below:
You were working with Company X and resigned. Company X asked you to serve a notice period of 2 months, in other words, to continue with the service for another two months for a proper handover. However, Company Y wanted you to join early and agreed to pay you the loss of payment for the 2-month shortfall. Therefore, the payment that you were earlier supposed to get from Company X is now being received from Company Y. Thus, the TDS has been deducted since it's a payment, not a reimbursement.
I hope it's clear now.
Regards,
Satpreet Kaur