Keys stick down after being played. I have cleaned, vacuumed, blown air throught he keys, etc. now change. I have taken the keyboard apart down as deep as possible and cleaned again, the keys still stick. It started with all the D notes, then expanded to many others. piano is basically unplayable

is it under warranty ?
if not
you may have to contact your point of sale to find their local repairer

if you cant un stick them yourself that keyboard will have to be taken apart

are the two keys ... white keys or black ...nearby or way apart
do the two keys drop loose..and lift up
or stay down
example will vacuum cleaner suction help lift the stuck keys or not

sales blurp says this
A spring-less hammer system
Scaled Hammer Action Keyboard

https://www.jbhifi.com.au/musical-instruments/casio/casio-cdp-120-digital-piano/91120

You have bad contacts on some of your keys. The keyboard has to be taken apart, and electronic contact cleaner has to be sprayed into the contacts to clean them. Press the keys repeatedly to spread the cleaner into the contacts. If the contacts are too badly pitted/rusted from water or other liquid damage, cleaning will not help.

Hi, If by "re" not working you mean note D then try the following.
Keyboard off, hold down top C key while turning on. This factory resets. Does D key now work - if not. Has it ever worked - if not then it could possibly be the ribbon connector between the keyboard and the motherboard. If one of the cables gets bent then this would stop all notes associated with that connection to stop working. This will only have occured if the keyboard has never played these notes or if it has been taken apart.

You could also try the self test mode : Keyboard off, hold C#,F, G# in the 2nd octave up whilst turning on, cycle through tests to sound if it plays all the notes one at a time then the sound chip is ok and it points to keyboard switching. If test mode does not come up in 2nd octave try 3rd octave ( cant remember which one it is from memory )

Let me know how you get on.

Hi, This and a lot of similar keyboards have gold flashed pads on the PCB and the keys press one or two rubber caps, with conductive pads in them, down.
Clean the pads with isopropanol, (and nothing else) and it will be cured 99% of the time. If a few notes do not work, especially after heavy use, then the rubber caps can be replaced.
Taking the keyboard apart is long winded because of the number of screws involved.
The job its self is simple enough, but take note of the order things go in and where the screws go.
Hope this helps, Chris.

Normally you have to clean the conductive rubber "pills" AND the circuit board traces they get pressed down on.

USE ONLY 99% isoprophyl alcohol on Q-Tips to do the cleaning and be gentle.

Use of other product like deoxit and other contact cleaners will wreck the contact material.

Likely the power adapter has failed if it uses one. Try a new one first.

If half the rectifier blows out, a very impure DC voltage is applied which will be heard in the audio output.

Probably something has come loose inside if everything else is normal.

Disassemble the device carefully. Look for cables or wires that may be partially or totally disconnected. If there are connectors, "reseat" the connectors. (Take them apart, put them back together firmly but not too firmly.)

If there is still a problem and you have a meter and are able to operate the keyboard with the unit open, you can compare voltage readings of those keys with nearby keys at any points you can find related to the keys. Compare with both keys up and keys down.

On some keyboards, you can bridge the switch contacts with an unbent paper clip to make a connection as though a key had been pressed. If you are comfortable with this and if doing that makes those keys play, then you have a mechanical problem related to the keys. Check for snapped plastic, etc.

If this is the kind of organ with the wire sticking out of the key that makes contact with the bus bar to create the note you will have to make sure that key is operating the same as adjacent keys. The busbars have to be clean and the contact wires have to be clean. Sometimes when cleaning the wires they will spring out of place and not make contact with the appropriate bus bars. Check that key against the rest and see what you find. Hope this helps.

There are 17 screws on the underside of the keyboard that need to be removed. The base cover can then be removed. This gives access to the keyframe assembly which can be removed.

This is a common problem with Yamaha keyboards. The problem is caused by worn-out rubber contacts in the keyboard assembly. In my old Clavinova CLP-500, there was one long rubber contact strip under the keys with two parallel strips of semiconductor material. The Clavinova circuitry determines key velocity by measuring the timing between when the key hits the first and second strips of semiconductor material. The harder you play a key, the less time it takes the key to hit the second semiconductor strip after hitting the first.
After years of playing the keyboard, the keys eventually cause tears in the semiconductor material and this messes up the timing measurement for key velocity. The only solution is to take the keyboard apart and replace the rubber contact strip with a new one.
I got rid of my CLP-500 four or five years ago and got a new CLP-170. The CLP-170 is now having exactly the same problem that the CLP-500 had. Yamaha has re-designed the rubber contacts in the CLP-170 so that there are now eight individual contact strips instead of one long one. The problem is essentially the same, though. You have to take the keyboard apart and replace the worn out rubber contacts.
Here are the part numbers for the rubber contacts that need to be replaced in the CLP-170: V8286600 Rubber Contact, 12 keys, D-C#   Qty. 6 V8286800 Rubber Contact, 11 keys, A-C#   Qty. 1 V8286700 Rubber Contact, 5 keys, D-C   Qty. 1
I suggest you also get a copy of the CLP-170 service manual, part number 001677. It has descriptions of all the steps necessary to take the thing apart and put it back together again. You'll also need a "rod" (which is just a long dowel), part number TX000670. Before you take the circuit boards off the keyboard assembly, you have to insert the dowel between the keys and the frame to keep the keys from falling back and getting in your way. A 5-foot long 1/4-inch dowel will probably work. (I haven't yet taken apart my CLP-170, and I don't have Yamaha's "rod," so I'm not sure if 1/4 inch is the right size or not. I'll report back here if it's not.)
Good luck, Howard