IOException several times a day

Several times a day I get the popup “Grindstone Failed to Save Your Data”.

What can I do to prevent these?

In the logfile there is this message:

– IOException: The process cannot access the file ‘C:\Users********\OneDrive - **************\Documents\My Grindstone Database.gsjdb’ because it is being used by another process.
at void System.IO.__Error.WinIOError(int errorCode, string maybeFullPath)
at void System.IO.File.InternalDelete(string path, bool checkHost)
at void System.IO.File.Delete(string path)
at async Task Quantum.Client.Windows.App.SaveDatabase(bool backgroundSave) in C:/Source/Quantum/Quantum.Client.Windows/App.xaml.cs:line 2019
at void Quantum.Client.Windows.App+<>c+<b__220_0>d.MoveNext() in C:/Source/Quantum/Quantum.Client.Windows/App.xaml.cs:line 1868

System info:
OS Name: Microsoft Windows 10 Business
OS Version: 10.0.19044 N/A Build 19044
Grindstone 4 Build 7380.29440

Update:

At first I thought writing in the OneDrive folder was the problem.

So I moved the file My Grindstone Database.gsjdb to my desktop…

That did not help.

Reinstalling Grindstone either.