File Upload Component

HI All,

I have a requirement to upload multiple documents and i am using file upload component. But in one scenario when  i am trying to upload the document with file name similar to  "5722996_TestFile8.23.18invoice8540226" the actual file name is not saving in the folder. It is trimming the value and it is saving as "TestFile8 23nvoice8540226". The first few letters before underscore is not present in the document saved in the folder. 

Please find the below code i am using to upload the documents in folder.

a!fileUploadField(

label: "Attachments",
target: tofolder(
ri!folder
),
value: ri!document,
saveInto: {
ri!document
},
fileNames: fv!file.name
)

Can you please let me know the root cause and how to resolve it.

Thanks in Advance.