It seems this doesn't give you all your data. However, we had no way to know.
If you are a beginner, it is best to stay in this forum. The other where you posted is for those with more experience.
Modify the following for your exact positions and lengths (an any typos I've made).
I've spread the code out as it is always easier to read, understand, and change, that way.
Remember, we only know what you show us. You showed us a short record, so Magesh23586 provided you with code for a short record.
Also note, that with something working, you can search for other examples of TRAILER3 and get a better idea of how it works, and also consult the manuals. You will learn more and faster if you do the work from guidance, rather than just copy and paste.