is there any way.. for you to get a potting media ..

sand in a pot.. is very hard to deal with ... its usually too wet.. or too dry.. and water does not move thru it very easily ...

half wood chips and half sand would not be great.. but it would be better ...

think of it.. this way.. trees roots need air as much as water ... and sand makes caked mud.. no air ... when in a pot ...

and i would put a pot that small.. in full bright shade ...

good luck

ken

I agree with the above, looks like it might need repotting into a slightly smaller pot with fresh/slightly looser soil. Looks like the soil is really moist there and it might be too much for it?
Hope it gets better!