Solicitor to write letter to an old client for bill payment

General information for the business: We sell construction leeds to businesses
Industry: Business
Legal topic: Debt
Description of legal work: Hello,

I would like a Solicitor to write a letter to my client, they have signed a contract to say they will pay for old construction leads sent to them. Now they are ignoring my calls and not answering my emails.

They owe £408 to date.

But they have broken the contract after 1 year without the required 2 weeks notification period causing me a loss of earning,

Every lead thats ever been sent to them has been fully transparent with reports and recordings, even an appeal process thats been used by the client on the majority of the reports sent.

Also I said if he pays his invoice on time I will allow his appealed leads to be approved even though many were because rejected because he refused to accept leads even during his agreed notification period.

I would like someone to highlight the multiple breaches of contract, and potential of additional charges if he refuses to go pay his balance.
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