Not Received Relieving Letter

I left last job in Aug and mailed my resignation then my HR called me up and asked me for the reason and accepted my resignation.After few days when I asked for my full settlement HR informed me that its a process which takes 45 days.When I completed that ,a new story that came across was that I have violated a clause as per the agreement which says I cannot join any competitor of that company.The company I am into now was the client actually.Although I am working with their client company but I am temporarily deployed here and my parent orgaisation is different,as such I am not an employee of their client as my payrolls are not on them.I made this clear to them still no response.Suggest me what should I do as I need to show my relieving letter in my company else my job is on risk.
Please respond at earliest.
Regards
Samridhi

Dear Samridhi,
As per law its illigal to get yourself associated directly or indirectly associated with any competitor or the client organization during or after your employment.So in this regard probably they are correct.Try discussing this amicably with your past organization so that you can get what you want i.e. your relieving late. If it doesn’t work then probably you can threaten them with the dire consequences but you may be the looser if it is pursued further.