Henry,a Manager at a Large Hotel and Convention Center,has Drafted

Henry,a manager at a large hotel and convention center,has drafted the following message to inform a customer that the ballroom that he wanted to rent for a company party is not available for the dates he had requested,but that larger ballrooms are available.
We regret to inform you that Ballroom A,which you had requested for an office party on 6 June,2011,is not available.However,other ballrooms are available,except that they are much larger.Please contact me at 456-123-7891 for more information or to make a booking.
Using the general guidelines for writing negative messages,rewrite this message so that it is more effective in taking the sting out of the bad news,ensuring its acceptance,and in maintaining goodwill.