They're waiting to see how it shakes out with the new person they're seeing, while simultaneously keeping their inbox warm. Is there an issue with the algorithm? Is there a glitch in the Matrix? But this time, try doing things differently. Time is precious, so focus on matches who are interested in meeting you in real life, face to actual face, and if someone is not interested in pulling the trigger, move on to the next fish.
And luckily, there are plenty of fish available to you at this endless digital buffet.