I have an IKEA LOVIKEN AA-291347-1 faucet. It leaks between the 2 handles at the connection.
I removed the screw behind, but I cannot remove the top center part.
Do you have any idea how I can open it to change the seal inside?
While you have removed the locating screw, there are usually 3 rubber (well nitrile or somesuch) sealing rings which are a tight fit.
So, you might have to twist and pull very hard to get them to release.
At least, that was the case when I took a similar tap apart.
Of course, lots of care needed to get it back together without damaging the new seals...