how to remove error "Reference to non-existent field "?

clc
clear all
clc 
clear all
fileNames=string(1:40)';
trialss=["1","2","3"];
movess=["RShoulder","RElbow","RWrist"];
pointss=["RElbow","RWrist","LT4Shoulder","LShoulder","LElbow","LWrist"]
axiss=["x","y","z"]
 datset.fileName=fileNames;
datset.moves=movess;
datset.trials=trialss;
datset.points=pointss;
datset.axis=axiss;
load dataset.mat

error is occuring

Reference to non-existent field 'L5S1'.

Error in incorporatingdataset (line 27)
infileName =
dataset.(fileName{i1}).(movName{i2}).(repName{i3}).(nfTime{i4}).(nsegName{i5}).(nrotName{i6}).(jointAngles); 
>> 

[Stephen23]

"how to remove error "Reference to non-existent field "?"

The answer is very simple: refer only to fieldnames that actually exist in your structure.