the main space key on my macbook pro 2010 keeps not working I already cleaned it carefully

An idea would be to look into DIY replacement key parts that are worn; &

should be do-able from the top, without a complete removal of keyboard.

A good example of source, and w/ instructions (that are free online)

for these three-piece key-sets, can be seen here:

• Apple Unibody Black MacBook PRO Laptop Keys (2009-2012) - replacementlaptopkeys

https://www.replacementlaptopkeys.com/apple-unibody-black-macbook-pro-laptop-keys-2009-2012/

Your 'build model' may vary from what's been stated; further research is

likely needed to be certain & order correct parts (no matter the source.)

For examples, general page of series versions; MacBook Pro:

https://www.replacementlaptopkeys.com/macbook-pro/

Because you can order single key-kits, each has Key-Hinge-Cup; & there

are variant builds from this original equipment source; be sure to match.

[This is usually an easier fix than replace entire top-case & built-in keyboard.]