I requested a copy of my contract but my HR department have said they have lost it / do not have a copy. I have lost my copy. By law should they have one on file? Where do I stand with requesting a copy? Can I put a complaint in? I have requested one as I have disciplinary meeting regarding my absence. I have genuine reasons doctors notes etc but feel like I am been treated unfairly as the manager has disliked me from the start. Would this help with my grievance I have raised?
You didn´t state your country, so I this answer give you more of a general idea. If you update your question we can be a little bit more specific.
In absence of a written contract, legal baseline and precedence will probably set the rules that apply.
If there really is no copy both on your and your employers side, setting up a new one in paper should be beneficial for both parties, as it will remove ambiguities and thus lower the risk of litigation.
I'm based in England, but I assume the principles are similar in many countries.
Legally a contract is a particular type of agreement - it is not a piece of paper. So as long as you and your employer have (or had) an agreement that you will work for them and they will pay you, you have a contract. If there is ever a dispute that goes to court you would be able to find evidence of the existence of this contract, e.g. documents or emails about your work, your bank statements, witness testimony that describes your employment.
If you also don't have any copy of the contract document then there may be limited evidence on what the detailed terms of the contract are. There are likely to be local laws that specify some details of employment contracts, "unless otherwise specified". In the case of any dispute relating to your work a court would have to use a combination of the laws setting these default terms, and evidence based guess work as to what your contract is likely to be.