ADVICE PLEASE‼️‼️‼️

So I have a 1 week old, I exclusively just pump and she takes a bottle due to a circumstance we are in..

I used to be able to pump 4oz, but the last couple of pumps it’s just been 2oz.

Could it be because she’s only drinking two at the moment? She was taking 3, and I was able to pump 3. I’m not saying it could be related,but I just don’t know. I’m feeling extremely discouraged.. and am thinking it’s just going to stop. I wasn’t able to breast feed my first, so I really wanted to with my second.

*i do have a supply built up but I need to keep it up.