SICK LEMON AND PEACH TREE
BOTH HAVE LEAF CURL, OOZING, CAVITY AT BASE
Certified GKH Gardening Expert
Your photos did not come through, unfortunately. It sounds like both are suffering from root rot. Most types of root rot fungus are not treatable once you notice the above symptoms. This is caused, mostly, by soil that does not have a chance to dry out between waterings.
You can make an attempt at correction. A fungicide will be in order, along with using a combination of DOLOMITIC LIME and WETTABLE SULFUR. Follow all product instructions
This article will help you with fungicide use: https://www.gardeningknowhow.com/garden-how-to/info/using-fungicides-in-garden.htm
In the case of complete tree removal being necessary, you will want to treat the area, and NOT plant any more fruit trees in that spot for a few years.
These articles will help: https://www.gardeningknowhow.com/edible/fruits/peach/peach-phytophthora-root-rot.htm