When you insert your SD card into your computer or laptop, there is a quick way to double check that your card is in the right FAT32 format.  See image below on how this is done once you have your SD card folder open to where you normally view your photos.  Computers are capable of reading several different SD card formats such as FAT, FAT16, FAT32, NTFS, exFAT, etc.  
However, phones prefer the standard FAT32 format; which works out well because trail cams like this format too.

*Note these instructions are on a Windows computer: