NDA and employment notice period

I have received “offer letter” and post accepting the offer, I received “appointment letter” with date of joining, “applicant form”, “NDA” and request to attach relevant documents. Below are the contents of clause 5 & 6 which are questionable and I feel these as unreliable to extent of forcing labour and mala-fide intent in deceiving employee. These clause comes after defining "disclosing party" and "receiving party" and after the heading - "It is hereby mutually agreed to by and between the parties as under:" 1. 2. 3. 4. “5. That the receiving party agrees to work with the disclosing party for at least 1 year and shall not leave the service of disclosing party during this period, except in the case of continued ill-health, in which case she/ he can leave the company by giving three months notice period or payment in lieu thereof.” “6. That the receiving party agrees, in case she leaves the company during the term of agreement, she undertakes to refund 50% of the gross emoluments