Bidspirit auction | Postage. Letter sent from Porto

Postage. Letter sent from Porto to the Covilhã Post Office, with a 40 centavos postage fee, without the additional 30 centavos postage fee, postage paid at $60 in Covilhã (postage stamps of §10 (2) and of $40 to 3.12). As it was not claimed, it was returned to the sender in Porto who had to pay the $60 centavos postage. Rare taxation at origin, due to return. File error.