The white cover on the piano's white keys came off, and the wood inside was exposed. What should I do? Andhadhun, can you fix it? Should I change the key?

Buy a bottle of "502 glue" or "all-purpose glue" (which can be bought in general grocery stores), evenly spread it on the white inside and the surface of the wood, then gently close it as it is, and press it with a heavy object (be careful not to let the glue deform! Otherwise, it will really be scrapped and replaced with a key! )。 As long as you are careful and patient, you can stick well as before. Usually it can be re-enabled the next day!