Error in Project Coding Mask "Edit screen is "1" too long" Message no. CJ62

Hi Friend's

In sandbox already i have Define Special Characters for Projects is as "2" (Length of key for coding)

Now when i go for defining Project Coding Mask by making following new entry in the spro

example "PR .0000000000.00.00.00.00 Dairy Process Project

after entering above details system gives following error

Edit screen is "1" too long

Message no. CJ627

How i can resolve this issue.

Thanks & Regards,

Sandeep