The protocol is that you should deal with his solicitor.
If he has instructed solicitors, and you continue to communicate him, he can allege to the police that you are then harassing him so you should deal with his solicitor to avoid that possibility.
If his solicitor will not reply, you are quite in order to tell the solicitor that if he doesn't reply, you will contact his client directly.
Can I clarify anything for you?
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