Supplementing formula while BF

I've been EBF bubs since he was born, no bottles or pacifiers, but now at 6weeks pediatrician suggested I supplement with formula because baby needs more. I've tried to introduce bottle and he wont take it. He doesn't seem to like the formula, he latches on the bottle until he tastes the milk and doesn't want it. How do I get him to drink it? I've tried half and half but he only wants my milk. I'm not producing enough it breaks my heart, but I just want him fed. He wont take the formula, I'm so overwhelmed 😭😩😭