$ambiente=$this->params();
$result=[];
try {
$params = ["txid" => $cobranca["txid"]];
$body = [
"valor" => [
"original" => $cobranca["valor"],
],
"calendario" => [
"expiracao" => $cobranca["vencimento"],
],
];
$api = Gerencianet::getInstance($ambiente);
$pix = $api->pixUpdateCharge($params, $body);