I planted this new passion fruit this spring. It had three vines growing from the root. But now one of them is dying. All leaves from that vine are withered. Please see the picture. Another one is not looking healthy either.

What could be the cause? I spray Serenade fungicide every other week on it and my other fruit trees. Is it a contagious disease? Shall I cut off the dying vines?

Thanks!

First vine already dead:

Second vine dying: