Material Documents missing

Hi Experts,

I have an Issue.Pls. treat this on Prioriy basis:

User created material document numbers from 5000000400 to 5000000410, in which numbers 5000000401 to 5000000409 are missing.The numbers couldn’t be found in the display nor in MB51,mb03 (material doc list ). In the display page of the missing nos the following message is displayed at the bottom of the screen as --- “ document does not exist in calender year 2007. “

Checked out the table MKPF, gave the mat doc num range from 5000000400 to 5000000410... THE RESULT WAS IT DISPLAYED ONLY 5000000400 & 5000000410.rest were not to be seen even in the Table MKPF.What could have been the reason? Pls. suggest!

//Mia