Import from Redmine fails with "RangeError: time value is not a finite number"

Hi,

I'm trying to evaluate YouTrack and started to migrate a few projects from our Redmine installation, but every project I tested ends up with this error ("RangeError: time value is not a finite number") and I can't figure out the reason. Any ideas on how I can find the cause?

Some of our tasks, in Redmine, are not yet estimated, so they don't have any estimated time set, but for testing I used one project with only 4 issues and set estimated time to zero on them, but even importing this project failed with the above error.

I'm using Youtrack version 2021.4.34352 and Redmine version 4.2.0.

Thank you.