Errors detected in the XREF

[codepirate69]

hello,
i know that this has been discussed before, but i still could't find a way to solve this
after around 4 hours of editing a pdf and adding study notes, i save and exit the pdf, and when i reopened i found that it was all gone
and giving me this error!

image.png

is there anyway to get my data back ?
i don't want it to fix the errors, i just want the edited pdf back.

[Daniel - PDF-XChange]

Hello, codepirate69

Generally such errors indicate the document itself is heavily damaged, if simply saving the file after you see this message appear does not resolve it, than I am afraid it may be impossible to recovery the lost data.
These issues are most commonly associated with non-specification compliant changes being made to a file, or the document being generated by less robust PDF applications, such as the Mac version of "Preview", or free online PDF conversion tools. If anything along those lines was used to create the file, that may have been the root cause, and the issue did not show itself until something else was changed according to standard procedure, and inadvertently some improperly formatted data was changed, lost, or moved.

If you can send us a copy of the document, I can pass it along to our Dev team for review, but in such cases, It is uncommon that we are able to recover the missing data.
If at all possible, you will want to check your records for an older copy of that file, before the issue occurred. If you do find one, please also include that, so we can perform a comparison between the two. This often helps us to identify and prevent such issues in the future.

Kind regards,