Excel Online Displays Incorrect Cell Format

Excel Online file will not display cell data in correct format. Adjusting the column width temporarily fixes the problem, which is unusual. Has anyone ran into this problem? 

Incorrect display below. Columns R and V are in Date formats, while S and W are on Time formats.

Somehow, adjusting column widths accurately displays values, but only for a minute or two.

Any advice on how to fix this?