audio file add in machine learning activity if occurs

https://www.mathworks.com/matlabcentral/fileexchange/50232-machine-learning-made-easy

above URL;

% I am Trying to play sound *** if activity == 'Walking' ***, but it's not working.

% Also I tried using if strcmp(activity,'Walking'); both result fail

% Please help........below code

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%add below function in "Human_Activity_Learning.m"

[y, Fs] = audioread('Walking Playing.wav'); % 1 second audio file

walking_sound = audioplayer(y, Fs); % Global variable: walking_sound

**********************************************

% In "plotActivityResults.m" function, I added play function

try

for ii = 1:height(humanActivityTest)

mycell1 = fieldnames(mdl);

myclassifier1 = strcat('mdl.',mycell1(3));

activity = predict(eval(myclassifier1{:}),humanActivityTest{ii,1:end-1});

if activity == 'Walking'

predclr = [1 0 0];

play(walking_sound);

else

predclr = [0 0.7 0.3];

end