First of all i want to say that is Love the plugin and it's features!
But I have a problem, it worked fine a couple of months ago but now it seems like the shop interface isn't opening. When I right-click on my Hypermerchant nothing happens.
And when I open and close my inventory the message "Thank you for you're continued patronage shows up in the chat.
I uninstalled and installed both plugins a couple of times. I've looked in the config and installed different versions of it but it still doesn't work.

Can someone please help me out?

This is the error in the error log, I don't know if this error is responsible for not opening the interface!

HyperConomy[2017-03-26 14:29:52.221]
SQL write failed 1 time(s). The failing SQL statement is in the following brackets:
[INSERT INTO hyperconomy_players (SALT, X, Y, Z, WORLD, ECONOMY, NAME, BALANCE, HASH) VALUES (?,?,?,?,?,?,?,?,?)]
Parameters: [[], [0], [0], [0], [world], [default], [Bob], [0.0], []]
org.sqlite.SQLiteException: [SQLITE_CONSTRAINT_UNIQUE] A UNIQUE constraint failed (UNIQUE constraint failed: hyperconomy_players.NAME)
at org.sqlite.core.DB.newSQLException(DB.java:909)
at org.sqlite.core.DB.newSQLException(DB.java:921)
at org.sqlite.core.DB.execute(DB.java:825)
at org.sqlite.core.DB.executeUpdate(DB.java:863)
at org.sqlite.jdbc3.JDBC3PreparedStatement.executeUpdate(JDBC3PreparedStatement.java:99)
at regalowl.hyperconomy.simpledatalib.sql.DatabaseConnection.write(DatabaseConnection.java:50)
at regalowl.hyperconomy.simpledatalib.sql.SQLWrite$WriteTask.write(SQLWrite.java:120)
at regalowl.hyperconomy.simpledatalib.sql.SQLWrite$WriteTask.run(SQLWrite.java:113)
at java.util.TimerThread.mainLoop(Timer.java:555)
at java.util.TimerThread.run(Timer.java:505)

You should report this on the HyperMerchant github: here