Unable to cast object Error

Hi Team,

I'm facing an issue in a sharepoint list which has a calendar view in it, at the time we edit an item to update some values we got below error:

Unable to cast object of type 'Microsoft.SharePoint.SPFieldChoice' to type 'Microsoft.SharePoint.SPFieldNumber'.

What would be the issue?, and as per the message it seems to be that one of the columns is causing the issue, but the thing is that it was working fine for long time without any changes to the columns or any action being done in the configurations until 2 days ago we got to see this message.

Thanks