Hello,
If you aren’t able to use the get and map functions.
Can you please share your json data(input / expected output) bundles as @samliew suggest? I can try it.
Also, confirm that your structure is always the same and it will always have that custom required data. If it changed or that custom data is not there then it’s failed or returned blank.
P.S.: Always search first, Check Make Academy. If this is helpful, mark it as a solution 
and 
Need expert help or have questions? Contact or comment below! 