Read/Write data to Storage and Data Missing

An app created in Swift that have read/write function to file. More than 80% testers doesn't have the issue. However, some testers have issues with reading from file (null values) after writing to file.

Only 1 instance of storage is used (storage.saveVector, storage.writeVector)

Anyone can shed some light? Same code base but why some users are encountering this issue? I read about concurrency and use of actor instead of class for thread-safety purpose. (https://www.swiftbysundell.com/articles/swift-actors/)

Should i init the storage every time before use instead of using the shared instance?

It was concluded that is issue with code implementation.

Read/Write data to Storage and Data Missing
 
 
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