Throw out that moisture meter because moisture meters can be very inaccurate. To see if it needs water, use your finger or, better yet, push a stick into the soil, pull it out and if soil sticks to it, hold off on watering.

Browning on leaf tips is often due to salt build up because of not pouring enough water into the pot. Rinse out the salts by adding water until it drains out. Repeat at least twice.

Hold off fertilizing until you see new growth and only use 1/4 the concentration you would normally use, assuming the tree is indoors for the winter.

I certainly agree with Vladimir concerning moisture meters. Unless you paid $150.00+ for your meter, your meter is NOT reliable. Cheap meters do a lot of damage to trees. Hopefully, you are not letting the tree set in the drainage water in the catcher. It is easy to see that the soluble solids content within the root zone is quite high, and needs to be reduced.