This plant hates too much water so keep the soil dry in between infrequent watering. Remove the debris off the top of the soil and check to see that only the ROOTS are beneath the soil, not the bark of your stem. Is that potting soil in your pot? Are you watering with tap water?
There are high salts in your soil either the tap water is contributing the salts and/or you've used too much fertilizer. See the white coating on your clay? I'd dump out as much of that soil as possible without disturbing the roots of this plant too much. Repot in bagged potting soil, not garden soil.
Purchase bottled water. This guy is built for dry environments with little rainfall. Let me know what you've been using for fertilizer and how often. Fertilizer and tap water cause salt build up in your soil and I love clay pots for plants like this as they 'breathe'...as the moisture evaporates from the clay it leaves behind the salts. Also make sure you scrub your pot before using it again. I'd also soak the pot for a few hours to remove the salt in the pores you are unable to see. Purchase a new pot, no larger than the one you have if necessary and make sure that it never sits in water. Raise the bottom of the pot off the surface of its saucer or the patio so drainage is enhanced. Do NOT use rocks or gravel for 'drainage' below the soil. That actually hampers proper drainage by causing a perched water table. JUST soil to within 1" of the rim of your pot.
It has few leaves because it is indoors with low light. It looks like you've given it plenty if not too much fertilizer. Fertilizer is NOT plant FOOD. Just chemicals it needs to make its own food. Because of the low light it only needs these few leaves to do that work. What are you plans this spring? Do you have a patio? Start on a covered patio then start to harden off to be in the direct sun. This is a slow process! Putting him in sun for 5 minutes for 3 or 4 days then increasing to 10 for another few days and so on. He has to thicken his leaves slowly to get used to the direct sun without burning. As well as the bark. Bring back in for fall by reversing the hardening off being out of doors to once again be able to be indoors. And that means no fertilizer before going back indoors. I'd use good old OSMOCOTE 14-14-14 and only for the period being out of doors...so ONCE a year, follow directions (2 tsp. ? sprinkled on top of the soil after you've repotted) ...do not fertilize for a good month after repotting in fresh soil. Water shallowly, this guy does not have a huge root system and are probably quite short. A pot that is shorter than wide would work well. Keep using clay. Bottled water...cool plant, he'd rather be in Africa than in England, amazing, huh!