Exide Industries — exide make ups battery in a non conditional complaint

I purchased the exide battery it 500 inva tubular invertor battery sl. No. 10g[protected] through your dealer m/s shree ram enterprises, nallasopara (East) against bill no. 746 dated 26th june, 2015 with the condition of 36 months guarantee and 12 months warranty. Recently the battery was not working in a good condition. I made a complaint. The complaint was made on 28th april, 2018 with ref. No. Wmha00014084v605. (In the grarantee period)
I have not received any response against the complaint made, even after repeated reminders