Hi there , my buyer doesn't seem to be receiving any messages I send him through Seabreeze msgs with my bank account details , is this a common thing ?

Seems odd to me
Try Contact Laurie the site owner to see if he can help.
His user name is Seabreeze. His most recent post is in the End of shooting the breeze thread. Clip on the username and it will give you the option to send him a message

Happy for you to test a transfer to me via my western union account - if that helps.