<p><b><span style="font-size:14px;">Dear {contact_name},</span></b></p><p>I recently made a purchase from your company and I wanted to thank you for your cooperation and service. My invoice number is {invoice_number} .</p><p>If you have any questions or concerns regarding my purchase, please don't hesitate to contact me. I am here to make sure I have a positive experience with your company.</p><p>Best regards,</p><p><b><span style="font-size:14px;">{business_name}</span></b></p>