I'm having this issue in vanilla Minecraft on my PC. I had a 3 powered rail line with 2 minecarts with a pig in each. I was using them to breed more to fill a larger farm of similar minecart design. I logged on one day to find both pigs and both minecarts vanished without a trace. I continued filling the farm using another pair of pigs. I log on one day and noticed 6 pairs of cows and minecarts had up and vanished.
I'm having this issue in vanilla Minecraft on my PC. I had a 3 powered rail line with 2 minecarts with a pig in each. I was using them to breed more to fill a larger farm of similar minecart design. I logged on one day to find both pigs and both minecarts vanished without a trace. I continued filling the farm using another pair of pigs. I log on one day and noticed 6 pairs of cows and minecarts had up and vanished.