notice u/s 143(1)

Dear sirs I filed an income tax return for AY.2018-19. As my client had no income there was no tax liability but refund was there for RS.96. Now I received a email (U/s.143(1)) stating that IT department won't refund below RS.100 so you have to pay entire demand. What I have to do now? How to pay that 96 rupees.