Change account number

I have changed the account number using the following script.

update gl00100 set actnumbr_2 = '1131' where actindx = '4'

It displays correctly in GP and everything is fine, except when I run the trial balance report, (Financial >> Reports >> Financial >> Trial Balance >> Summary)

It no longer picks up any of the values in that account, how can I alter the account number and still have the trial balance working?

PS I have tried the PSTL and it wouldn't update this particular account for some reason, so I did it manually.