Write a letter acknowledging correspondence indicating Postal delay.

Dear Sir,

This is to state that we would like to thank you for your order. However, with regret we would like to inform you that we cannot fill your order due to an unexpected shipment delay from our overseas suppliers.

We would hold your order for arrival of the merchandise, and ship shortly thereafter since unfortunately, we cannot provide you with a specific shipping date at this time.

Thank you for your anticipated patience with regard to the delay.

Thanking You

Yours truly,