Long term fuel trim not working (No value/ not trimming)

Hello
I need help
My car is Nissan Sentra 2008
Long term fuel trim for six to eight months now doesnt show any value or is not trimming in all driving conditions.

Any help how to solve this?

Check to see if you are in closed loop. If you are, try another scanner.

Yes, its enter close loop as you can see from the attached picture.
Have checked with three different obd scanners, same problem.

Sorry, didn't see the picture before. Your short term is at 25. I would correct that issue first, get it under 10%, then see what happens with the long term, or not even worry about it.

It marvel me, because in all driving conditions its stays at 25%, when i disconnect the sensor ltft still says 0 whiles stft is also O.

But irrespective of stft value, ltft always give a value (ie +9, -2...)

Have you tried to manually move the trims by creating a vacuum leak or introducing an alternative fuel into the intake?

For some reason, a lot of Nissans are like this. I've seen variations between scan tools and found that they only consistently report short trim data. If you have a scantool that reads enhanced data, check the alpha % and cont learning value.

There seem to be different strategies at work regarding Nissan and fuel trim corrections. A typical strategy was to crank up gradually the short term fuel trims (positive or negative) as needed. If they reached 20% (?) without a sufficient response from th O2 the system would go back into open loop and after a short while enter again into closed loop repeating the cycling. Your model 2008 may apply this or a similar routine.