Bikanervala / Bikano — poor quality (stale) of cham cham

Address:

Devli Road, Khanpur,, New Delhi, Delhi, 110080

Have been purchasing Bikano CHAM CHAM, thru' Flipkart Grocery.
On 02.09.19, ordered 1 No. Bikano CHAM CHAM, thru' Flipkart Grocery, which was supplied & Invoiced by M/s Shreyash Retails (P) Ltd. on 05.09.19, vide Invoice No. FABYDW[protected] dtd. 05.09.2019. Product Batch No. B8BBA, Date of Mfg. 11/08/2019, Best Before10/02/2019.
On 24.09.19 night, when opened the metal Container and started eating, piece smelled and tasted bit sour, as if it has gone stale. Immediately checked for its Mfg. and Best Before dates which are quite OK.
Next morning, tried to contact at customer care No. but could succeed only next or next to next day and assured of replacing the same within a week time.
I've kept the stale container in my Refrigerator but no reply from BIKANO.