Hi there I'm someone who lives in southeast Asia. The weather here is hot all year round.Recently I've bought four cacti - and one is already dead.I water them twice a week and I think one of them died due to overwatering. The cacti are put in glass jars that have no drainage holes at the bottom.cacti are about 2 inches tall. The one that is dead is a bunny ear cactus. This cactus started leaning over and the bottom part discolored. It smelt horrible. I have attached a photo for reference. When I touched it the whole bottom was soggy and wet and had no support. It had three "ears" attached. I threw away the big part with the roots as about 3/4ths have rotted away. I don't know whether to replant the "ears" now. Should I? Besides this I have another plant(also attached pic)I don't know if this plant is a succulent or what species it is.It is leaning as well. Bottom part turning black. Other leaves on bottom part turning dark dark green, losing white spots, becoming hard and when you touch the plant it feels like it can twist and it is coming off on layers.I suspect it is overwatered,too. What should I do? Should I cut it off? I really don't know.I want to save my plant! Feeling so anxious over this. Ps update.. The file upload is not working on my phone so will upload pics asap. Thank you!