please help with dying plant

I'd be most gratefull if anyone could give advice on this plant, one head is turning brown and the problem seems to speading to the other heads slowly but surely. Last growing season it was in the ground but it started having problems so I moved it to a pot but things dont seem to have improved.

I'm not sure what has caused this, it doesn't look like red spider or bugs of any kind.

I would get it out of the bowl as soon as possible and examine the roots. If the plant body is like this, I'd expect the roots to be weak or diseased or rotted. If so, there's not a lot of hope, other than to top as many of the heads which are still green, and to try to root them down.

It looks like M. polythele, which doesn't often branch or pup, but its an old plant and I'd try to save what you can.