The other side does not stay silent. They push back. They send letters that ignore your position, raise the temperature, threaten escalation. Most people fold at this stage, because the pushback is designed to make them fold. The work of this lesson is to give you scripts and a posture that hold under pressure.
The three forms of pushback
First, the soft brush-off. Their reply ignores your notice entirely and restates the original demand as if your letter never existed. Response: a single short letter referring back to your notice by date and reference, noting that no rebuttal has been provided, and stating that the matter remains in the sequence you set out.
Second, the dismissal. Their reply tells you, often with a touch of contempt, that your arguments have no basis in law, that the legal-person distinction has been rejected by their courts, and that you should pay or face consequences. Response: a Notice of Default. Do not argue the point. Do not try to convince their officer that they are wrong. Note that they have not addressed your specific points, that an unrebutted notice stands, and that you are recording their dismissal as a refusal to engage with the substance.
Third, the escalation. Their reply or their next letter announces a court date, a liability order, a bailiff instruction, or a debt sale. Response: continue the sequence with the appropriate next document, served also on the new party. A bailiff firm gets a Notice of Conditional Acceptance and a notice of trespass for any visit. A magistrates' court summons gets an affidavit on the file and a written demand for proof of jurisdiction. A debt collector gets a fresh conditional acceptance demanding the assignment documents.
Tone scripts
Calm. First person. Lower-case name. Blue ink. Signed by hand. No insults, no shouting in capitals, no quoting of dramatic-sounding maxims you have not understood. The strongest letter is the one that reads like a calm man stating his position for the record.
Hold the line
You are not trying to win an argument with their staff. You are not trying to convert their solicitor. You are building the record so that when the matter reaches a point where someone has to make a real decision, the record speaks for you. Pushback is part of the process. Each round of pushback that you meet with the next document in the sequence is another point on the record where they have failed to engage. That is your work.