Protocol is that solicitor, or indeed you, should attend as a matter of courtesy to the Court. It would also be helpful to the Court if they were advised in advance by the solicitor that the case would not proceed so that the Court can perhaps schedule something else in.
If no-one shows up or does anything in advance, it is regarded as a serious breach of Court etiquette - solicitors are officers of the Court and have duties and responsibilities towards the court. Not to show up and let it be thrown out is just rude.
mf