Q.Container Meyer lemon tree fruit not growing
I have a dwarf Meyer lemon tree which has been growing in a 3/4 oak wine container for several years. It has always produced a generous amount of good-sized fruit in the past. I fertilize with slow-release organic fertilizer from January through August per package instructions. This year the tree has a lot of fruit but they are not growing more than the size of a walnut to a large ping pong ball. It is like they are in suspended growth. I water every day and the tree gets over 8 hours of sun. I live in northern California and it gets very hot here but it hasn’t been a problem for the lemon tree in past years. We did not have much cold weather or rain last winter. Can you give me some help as to why the fruit is not growing? Thank you.

I would increase the watering. If the container is drying to quickly, water twice a day.
This should help the fruit grow and ripen.
Here are some links to refresh you on the care needed.
https://www.gardeningknowhow.com/edible/fruits/lemons/growing-meyer-lemons.htm
https://www.gardeningknowhow.com/edible/fruits/citrus/tip-on-water-requirements-for-citrus-trees.htm