How to deal with a hard-to-reach client

ksbtranslation wrote:

Our translator has just completed a large project assigned by a Proz member whose profile is registered as a famous IT company in China. The huge payment will be due tomorrow. However I found it difficult to contact her by phone or email. No telephone number or address is listed either in her emails or PO.

I tried to access the numbers found in her blueboard and company website but unfortunately they could not put me through to her because they require her Chinese name. There are some employees using similar names and none of them is in charge of the translation!

So far she only contacted me when she had another task for us to do or confirmed the receipt of our delivery. she never complained about our translation.

I am really worried about this since I have no evidence to claim the payment. All I got is a plain PO which does not include any detailed information about her company, tasks and payment. She could easily run away with it although she promised me that she would process the whole payment on Wednesday, 25th February 2009.

I wonder if you could share your ideas.

Thank you in advance.

Best regards,
Iwan