how can determine phase from FFT

I have written a code, where I have matrix dimension 1801 by 88 and when i am running the code, phase is obtained. But in foor loop the first column of phase is repeatedly coming for other 88 columns. But in amplitude, it is coming properly i.e. 901 by 88. In phase, matrix dimension is 901 by 88 but in which same values are coming repeatedly for all columns. Please help me regarding this.

clc;
clear all;
load data.dat;
time=0:2:3600;
time=time';
nn_ss=data(1:1800,1:88);
 for jj=1:88
    ss_nw = nn_ss(:,jj);
    Ts = mean(diff(time)); % sampling time
    Fs=500; %sampling frequency    ** It should be 1/Ts
    Fn=Fs/2; %Nyquist frequency
    L=length(time);
    Y=fft(ss_nw);
    fts=Y/L; %Normalized fft
    P_amp2=abs(Y/L);
    P_amp(:,jj) = P_amp2(1:L/2+1);
    P_amp(2:end-1,jj) = 2*P_amp(2:end-1,jj);
    f=Fs*(0:(L/2))/L;
    phase(:,jj)=angle(Y).*180/pi;
    phase1(:,jj)=phase(1:L/2+1);
    %phase1(:,jj)=phase(1:901,jj);
    ly=length(Y);
    fs=(-ly/2:ly/2-1)/ly*Fs;
 end