What's eating my Hot Lips

[MaggieMcGill]

Hi, hoping someone can help with this, fairly novice gardener here. I bought 3 hot lips plug plants early spring. They have been doing great and have grown lots but something seems to be eating the leaves. They are just disappearing and it's like a clean cut at the steam. One plant's remaining leaves have also started going a funny brown/red colour and it doesn't look healthy. They are all in pots.

[traviata]

I'd suspect leaf drop due to drought, actually, rather than eating. Are the leaves on the ground or have they disappeared entirely?

[MaggieMcGill]

No leaves on the ground, I have found the flowers on the ground but not the leaves. This one is at the back of the house, it is the healthiest looking but it's still missing leaves.