India Post — rs 10 coin not accepting in india post horamavu branch

Address: 560043

Hi,
Today, i went to submit the speed post, in their premises they had written
That rs 10 coin can be circulated, but when i tender rs 10 coin, he said it is been circulated, but we don't accept it, so when i asked him, why he was posted, such note, he was arrogant to reply back.

Please take care of this branch,

Horamavu branch post office,
Bangalore, next to bbmp office.