Those bright new leaves are looking great though! I had one which I had bought and it lost its first leaves, too. But then the new ones would last longer. Kind of as if the leaves that were grown elsewhere were replaced at first and then the new leaves grown in the new home would last much longer. In the wild here when I see one and try to take it home it’s the same story: any leaves that were there originally quickly die off and the new leaves last longer.
I also saw that new leaves would always grow larger than the old ones, except when I forgot to fertilize or water. But it takes a while for leaves to grow truly large. Maybe it has to do with the roots or something.