Scale to be considered for comparing electronegativities of nitrogen and chlorine The Pauling scale gives the $\chi$ values of $\ce{N}$ and $\ce{Cl}$ to be $3.04$ and $3.16,$ respectively, but the Allen scale gives the $\chi$ values of $\ce{N}$ and $\ce{Cl}$ to be $3.066$ and $2.869,$ respectively.

Another point that should be made note of is that the most electronegative element as per Allen scale is $\ce{Ne}$. So, why is it accepted in the first place? And whose electronegativity is actually greater?
Please take into account that there are a lot of different ways for calculating electronegativity.

1) Pauling obtains it by comparing the energies of dissociation of the three diatomic molecules AA, BB, and AB, stating that H electronegativity  is 2.1 !  Unit : √energy

2) For Mulliken, it is the average value between the electronic affinity and the first ionization energy of the atom. Unit : energy

3) For Allred - Rochow, it is the force acting between a valence electron and the charge of the atom when the other valence electrons are removed. Unit : force

4) For Sanderson, it is the average electronic density of an atom divided by the average electronic density of the corresponding atom of inert gas.No unit.