mc version:1.12.2
mod version:1.12.2-r135

this is coffee maker gui.
If put a bucket of milk at slot 1, 2 pieces of sugar at slot 3 and 4, and 2 magma creams at slot 5 and 6, the result is a cup of coffee with buff Fire Resistance 2(20s), Speed 2(30s)[expected Fire Resistance(2:20) and Speed (2:30)]. But if change the milk into slot 7, the result is correct.

Working as expected