‘Nigeria spent more than $2.6 billion in 2016 to address the humanitarian
challenges caused by Boko Haram terrorists, Chief of Defence Staff,
Gen. Abayomi Olonisakin, has said.’

Note this $2.6 billion was not spent on ARMS or the WAR itself but on ‘humanitarian challenges’

Where, when and how?

This is what the idle and useless senate should be investigatng instead of investigating how to wear uniforms!