I think you should try the best OST to PST converter Tool and follow its simplest steps to perform migration procedure with all emails, contacts, calendars, tasks, journals, etc. The OST to PST converter software enables data recovery from the corrupted OST files into outlook PST files effortlessly. However serious your OST corruption is, fret not as Mails can help deal with it and recover all information from the OST file. By using this tool, you can convert OST to PST, Zimbra, Gmail, EML, EMLX, vCard, ICS, MSG, Office 365, Live Exchange server, MBOX and etc. The software is compatible with Windows OS and supports all versions of MS Outlook, including Outlook 2019.
And to export the OST mailboxes to PST, follow the simple procedure:
Go to Files >Open & Export and click Import & Export.
Select Export to a file;
then click Next.
Select the second option—Outlook Data File
More info- OST to PST COnverter