You need no longer get registered below GST regulation. In case you your annual income is greater than 10L and staying in positive prescribed states then you have to get GST registration. The purpose on your customer’s insistence on your registration is they cannot claim input tax credit score above that they've to pay & claim the GST under Reverse Tax Mechanism since you are not registered. So it is better to get voluntary registration although you are not accountable for registration https://123gst.com/gst-registration/registering-in-gst