ebf and casually pumping......help

So I am ebf my 5 month old and only pump when needing to go somewhere without him which is very rare, I have never had a problem pumping before in the earlier months I was able to pump 5 plus Ozs within 5-10 min but now I can pump for 20 min and barely get 2oz from both breast. I know some people say when you ebf your breast don't respond well to a pump because they are so use to baby draining your milk. So was wondering if anyone else has this problem and has any tips on what I can do to be able to pump enough for him so I can leave for more than 2 hours ☺️.