Unable to reverse the Receipt as the reverse tab got greyed out

Hi Experts,

I have created a Receipt which is Un-applied whose Receipt Date= 3-Nov-2015 & GL Date is 3-Oct-2015 which the user has created by mistake. Now when the User is trying to reverse the receipt from his responsibility, reverse Tab is Greyed out.  But when I try to reverse the receipt from Super User responsibility, Reverse tab is active.

1. why  the Reverse tab is greyed for one responsibility & active for other responsibility.

2. User has done many reversals in the past from the same responsibilities. Please advise

Receipt Date: 3-Nov-2015

Receipt GL date: 3-Oct-2015

Please advise