大大们请教这句英语怎么说

Shipping companies that:D / O in the hands of shipping companies,you can change the B / L.D / O in the hands of customers can not change the B / L.Shanghai shipping company earlier has been to identify the port of destination,the customer has been using B / L for the D / O,can not be changed in the Shanghai B / L a.Only one destination port of destination in Bangkok to apply for changes in B / L,shipping companies can only assist in Shanghai.