Post office refusal to issue Dependent BRP due to spelling mistake in BRP Letter

[appumehta]

I need your help and Guidance with regard to BRP of my dependent son.Post office refused to give his BRP because the letter issued by UK Visa and immigration department for collecting BRP had a spelling mistake in his surname(ommission of letter'E') and as per them identity could not be established because passport has surname different from letter.I checked my Visa application form also which has correct surname spelling.It seems this is a typing error on their part.Also, Post office informed me that they shall return the BRP to Home Office and I should get in touch with them.I immediately approached UKVI through the channel available in such cases which is an online form.This was replied to by BRP collection team asking me to reply with a cover note explaining the situation again and full UK address where BRP can be sent.They also stated that meanwhile they shall get the BRP from Post Office. I replied to their mail stating the details asked for on 3 September, 2017. After that I haven't heard from them.I have sent many reminders through mail and through the online forms again but haven't got any reply.
Kindly Guide me, help me.