How can I check if BT has received the 4g router I sent back several weeks ago
They normally send out an email when it has been received.
As long as you have kept your proof of posting you could phone BT Billing 0330.1234.150 and they will update your account.
The Royal Mail tracking site should also say if it was delivered and when.
I didnt get a receipt - foolish I know
Just didnt think straight oh well
It can take three to four weeks for accounts to be updated.