Event is still saved when an invalid value is entered in "Floor" in the "Sessions & Speakers" page

[khangon]

Describe the bug As the organizer, I input to the Floor fields some values that include at least a "letter" for Microlocations or Virtual Online Rooms in the Sessions, Microlocations, Session Types setting, then tap on the Save button without Error. In the Overview>Event Checklist, I selected Sessions, Tracks & Microlocations, there is no value for Floor fields.

To Reproduce Steps to reproduce the behaviour:

1. Create an Event.
2. Input a valid value for the required fields.
3. Turn on "Sessions & Speakers".
4. In block "Microlocations or Virtual Online Rooms", input Room fields and Floor fields with the value including at least a "letter".
5. Save the Event without Error.
6. In Overview>Event Checklist, select the Sessions, Tracks & Microlocations.
7. Observe the value in the Floor fields.

Expected behaviour All valid input values are saved, or the error message should be shown for invalid values.

Screenshots

[mariobehling]

It is possible that there is no floor information.