pdf file corrupt

when i add annotations on pdf file and save it, and i open the file after that, i find the file corrupted but not all the time i find this bug ?
This issue exists also in your demo project.

Sorry, but i have this big issue also, some times i get the annotations saved fine, some times i get the file corrupted.
Also how can i import annotations instead of(/with) this solution, how can we export import annotations manually can you support us with the code?.,
Sorry but we have to deliver the application and we're very late, so please give us a quick response.

I've just seen you was creating a bug ticket on the support platform.

About the function request: actually there is no way to export/import annotations using our library.
You should programmatically create them and while creating you should store action to generate annotations within your files or database.

I confirm the bug that sometime corrupt file while adding annotation.
We're working on a fix.
I'll update you both here and in the support ticket platform.

Thank you for the reply, god help you, and we're waiting.

Also, how can we add annotations programmatically to the page, can you support us with the code, for at least (line, free drawing, rectangle, ellipse, highlight, text comment)? until you fix the bug, for our urgent delivery.