There are several types of "cleaner", some of which leave an oily residue, which may cause problems or attract dust in some situations..
The best for general use is just plain isopropyl alcohol (IPA), which does not leave any residue and is harmless to most components.
It's also possible that the cleaner washed some dust or dirt to a different part of the unit, where it is now interfering with the keyboard contacts.
Or it's just a grotty connector, not making full contact..