Proving I've got Mauritian citizenship ?

Hi hope someone can help / advise me. Both my parents are Mauritian but I was born in UK. I applied for and was granted Mauritian citizenship around 10 years ago when visiting Mauritius. I was sent a very small piece of paper a few months later in the UK which was all the proof I had. I'm visiting Mauritius in  2-days time and wanted to start process of applying for a Mauritian passport however I cannot find that piece of paper proving I have Mauritian citizenship . Is there somewhere / somehow a method / place (phone number etc)  I can go to when I'm in Mauritius where they will have a 'record' of my previous successful application and I can pay to get a 'copy' to prove my Mauritian citizenship, I understand I have to apply for an ID card before the passport application too ? Any help really appreciated ! Thank you.