When using a design form some of the formatting changes might not be compatible or might be made by mistake and cause issues of how a screen is viewed. For example two text fields might overlap or disappear.
The way to resolve this would be to either revert the change made or reset the Design form on a certain window which will reset the design form to its original form.
To reset a design form:
Open the type of record which has the formatting issue.
Click Design form and then click Reset.
Re-open the record.