Unfortunately, you cannot. Once you have retained a lawyer, you are no longer permitted to contact your spouse’s lawyer in the event that yours is unavailable. This is done to ensure one stream of communication. Furthermore, you retained a lawyer for a reason, which is why all communication then goes via the lawyer. On a final note, your spouse’s lawyer is, also, not permitted to talk to you if you have retained a lawyer of your own. They will advise you of this or, simply, not take your phone call.