A4 size from sra3

Hi! Wat started as something simple has turned into a problem!

I hav a business cutter that cuts a4 size! I want to use it!

There are set margins and bleeds which I hav setup!

The problem is when I impose it to sra3 which you would think it’s a simple 2a4s(my printer and paper is sra3) the a4 is smaller than a normal a4 and can’t be used by the business card cutter! I don’t understand why and tried various ways (10 times) each time is the same- it’s smaller than a4!

Is there a cc software that cud cure this! I just need an a4 template print( 2 from sra3) many thanks!