Error occurred when I switched from MATLAB's generic OCR to my self trained OCR.

location= 'filepath\*.jpg';
ds = imageDatastore(location);
fid = fopen('noPlate.txt', 'wt');

while hasdata(ds) 
    img = read(ds) ;             % read image from datastore
    gray = rgb2gray(img);
    gray = medfilt2(gray, [3 3]);
    
    ocrResults     = evaluateOCRTraining(gray);
    recognizedText = ocrResults.results;
    
    % This portion of code writes the number plate
    fprintf(fid,'%s\n', recognizedText);      % to the text file, if executed a notepad file with the
    fprintf(fid,'%s\n', '\n');
                         
end
fclose(fid); 
winopen('noPlate.txt')



% evaluateOCRTraining function: 

function [ocrI, results] = evaluateOCRTraining(I, roi)
trainedLanguage = 'file_path';
layout = 'Block';
if nargin == 2
    results = ocr(I, roi, ...
        'Language', trainedLanguage, ...
        'TextLayout', layout);
else
    results = ocr(I, ...
        'Language', trainedLanguage, ...
        'TextLayout', layout);
end

[philip curran]

i am experiencing the same issue, have you managed to resolve it?