Franch Express Courier — My courier is not reached to my customer

Consignment number: [protected]
I couriered a product from kolathur to otteri..
In ur website it shows as delivered with customer sign.. But she complaints as it not my sign and I didn't recieved any parcel...
I enquired about this in ur office([protected]) yesterday he replied that he ll clear it next day but not yet courier delivered as my customer complaint.. And now they r not picking up phone...
Due to this, It affected my business.

I need valid reason for this...