SQLSTATE [HY000]：常规错误：933 OCIStmtExecute：ORA-00933：SQL命令未正确结束（ext \ pdo_oci \ oci_statement.c：148）

Question

I want to update a value in a table and it keeps showing me the same message:

SQLSTATE[HY000]: General error: 933 OCIStmtExecute: ORA-00933: SQL command not properly ended (ext\pdo_oci\oci_statement.c:148)

Code:

function modificarEstado($conexion, $nif,$email) {

    if(devolverEstadoconEmail($conexion, $email)=='Activo'){ 
        try { 
            $consulta = ("UPDATE CLIENTE SET ACTIVOBAJA='ACTIVO' WHERE DNI_CLIENTE=$nif"); 
            $stmt = $conexion -> prepare($consulta); 
            $stmt -> execute(); 
            echo $stmt -> debugDumpParams(); 
            return true; 
        } catch(PDOException $e) { 
            $_SESSION['excepcion'] = $e -> GetMessage(); 
            echo $_SESSION['excepcion']; 
        } 
    }