Girls getting less chatty/compliant after going to text

I don't know if this is a common fenomena or just me fking something up, but I have no trouble scalating on the apps and getting girls agreeing to a date(spmetimes very clearly sexual) and sending me their number, but it seems they always go flakey, non responsive, hard to get etc when over text. It feels like they feel it's "getting real" and put up a wall, which I fail to overcome. I have a very similar feeling when talking to girls on the app who I matched and are too far from me to actually set up a date, and so they are always more talkative and sexual, saying things like "If I were in your city we would totally hook up" etc., like the fact it is not doable makes them confortable. So far the only idea I've got is trying to build some more rapport both on the app as well as over text( I usually just go for "hey, sup" followed by setting up the date), since I usually number close them quite fast on the app. Any help is really appreciated!