Not like dropped more like it's too slow that when it resolves the bitcoin that had RBF applied meant that when it was delivered it got no bitcoin to deliver anymore. Think of it this way, you ask for someone to deliver you a package but they take about 3 days to arrive to get the package and deliver it to the address so you hire another one that will deliver it to the same address (same address for the sake of example) but this time they arrive in 12 hours but you have to pay more because they're faster.