Business Rule running twice when approving from related list

[Tatiane1]

Hi, when i try to approve a register in sn_compliance_policy directly from the related list, it should give me an error message when a field is not filled. I have a Business Rule to check this, abort action and show the error message, but its showing the same message twice. Looks like its running twice, in the Business Rule debugger its showing 2 registers of this Business Rule but the gs.log shows only one log.

Could someone help me with this problem? 

Regards.

[Tatiane1]

It runs before updating to Approved.