if you have linux installed on a virtual machine, sometimes you may want to expand the storage but that means deleteing your swap partition, because they are stock at the end of your main partition in between it the the free space.
When you delete it and add it back again it will not be detected on boot. we are here to solve that.
if you run the following command you will see the UUID of the old swap partition:
grep swap /etc/fstab
this command will the you the UUID of your partitions:
blkid -c /dev/null -o list
find the one with fs_type swap and copy the UUID and replace with with the one already in the file /etc/fstab