It may be thrips or aphids or scale. All of them are sucking insects and can cause puckering and leaf distortion
These are links to identifying citrus pests with descriptions of common problems
https://ucce.ucdavis.edu/files/datastore/530-15.pdf
https://www.vitalbugs.co.za/citrusgallery.asp
Citrus thrips link
https://cals.arizona.edu/crop/citrus/in ... thrips.pdf
To manage aphids, scale and mealy bugs. Put out ant bait (I use outdoor terro), you can also put tanglefoot around the trunk of the tree a foot or so up the trunk. It will need to be reapplied when it is no longer sticky.
pests can be blasted off the very young leaves with a jet of water.
Horticultural oils can be used for control. Follow label instructions
Some of the leaves in the background look like they may have scale or aphids. They usually are found lined up along the midrib of the leaf and aphids on very young leaf tips. Their feeding will cause the leaf to feel sticky and sooty mold might blacken the leaves.
Citrus may have more than one problem. Aphids, scale and thrips often appear with the new leaves and when fruit are forming and can occur at the same time. The best defense is a healthy plant. Make sure it is fed and watered well and has good air circulation. Citrus do not like heavy pruning so it is best to prune a little at a time, all the time. I cut off any branches that are growing up higher than 8 ft and I thin the branches so more air and light can get through the canopy.