The problem with dating an sp is their lack of sex drive. When she fucks 20-30 other men per week, it just feels like she has no interest in it with me.
Don't take this the wrong way but that can be on you. Even though you're paying for it, you can't just show up to be 'serviced' - I think that's the wrong attitude.
You should honestly go out of your way or outside your usual routines to impress her a bit. Dress well, smell great, shave, etc. Find out her likes, bring her drink/food/treat/candy.
I'm not saying it's ALL on you as yes, if she sees a bunch of guys before you, how excited can she be? 'Oh wow, my 15th dick of the day, how rare!'....yeah yeah I get all that.
But it's also on YOU to rev things up, make the encounter interesting, be a bit unpredictable, be fun.
I'd do things like bring rose petals, candy, drinks, a small gift, nothing crazy. My point is just showing up with cash in hand isn't sufficient especially if you're seeing her later in the day.