Contact Us By Using Our Portal!! Email (HIPA compliant),Appointments,registration,payments,upload your picture, and most important tell us what is wrong and your previous history. Click Here for Portal. Main Office 603-818-4712. Office Fax: 603-260-6937. Billing (Colleen): 603-744-9430. Mobile Site Adress: m.markdetweiler.org. Toggle Navigation..