Assigning “Usage” DB Permissions, Postgres

More programming fun!

OK this time around I'm trying to create a table with the statement,

CREATE TABLE tablename ( recnumber SERIAL  PRIMARY KEY, recordvalues VARCHAR ( 500 ) NOT NULL, datecreated DATE )

And it basically works, and I can add records using the dba account. However when I try to add records using the application db account I get the error,

permission denied for sequence _seq

A search engine claims that I need to assign "Usage" permissions, but this is turning into a rabbit hole of then needing to assign 'Usage' rights specific to something called a 'sequence.' But I feel like that will only be a dead end.

Am I better off granting . privs to the application service account? Or perhaps just running the application using the dba account? Or maybe I should switch back to Mysql?

It seems like with postgres there are a lot of hoops to jump through but that the nuances are reducing than adding to the flexibility of what I'm able to configure as a DBA. This is not a rant post and I am quite happy to switch back to Mysql if that's what everyone else is doing. No point in using Postgres if it's a step backwards.

Thanks in advance!