Q.How can I rescue our Citrus Mitis
We have 3 Citrofortunella mitis (Citrus Mitis). 2 weeks after changing the pots (with holes and gravels in their bottom), I gave them liquid fertilizer containing iron. After that time, some of the green leaves have fallen and then little by little the leaves become brown and wrinkle and then fall. Now the trunks have become brown and dry. Also, the soil is always wet, even if I do not water them for 2 weeks. How can I rescue them?
The constant wet soil is a concern.
The growing medium is to heavy and needs to allow drainage.
The tree soil should dry slightly in between waterings.
Here is an excellent article with specifics on how to grow and feed the potted citrus.
https://www.gardeningknowhow.com/edible/fruits/citrus/growing-citrus-trees-indoors.htm