No customer service

Good day

I have lost my invoice when Restonic replaced my bed about 3 years ago. I have been emailing them and sending them messages from their website but to no avail. Our mattress are still under warranty as this mattress was already an replacement of a mattress that pulled loose on the sides. I really would have hoped to get someone that can contact me so they can look on their system as too how long we have the current mattress.