[GNC] Keep running into "Could not get lock file for postgres..."

[Bryan B.]

For some reason, GnuCash has started having some issue when I'm opening it
where it will say "Could not obtain lock file for
postgres://postgres@localhost/gnucash_personal"
Then it gives a few options to use the file anyway, such as to use it in
read-only mode, etc.

I found a temporary work around by opening it anyway, saving it to xml,
dropping then recreating my postgresql database, and then reopening the xml
file and resaving it to the postgresql database.

Any ideas on why this would be happening and how to resolve it?