This discussion clarifies the distinction between personal income and business income for sole proprietors, particularly when GST is involved. It explains that if you have income unrelated to your business, GST might still apply if you issue an invoice. The advice suggests that such unrelated income, when invoiced, could be taxable under Profits and Gains from Business or Profession (PGBP), and GST would be applicable.
26 February 2020
If a person have business and also have GST number. but person have other income source not related to Business. In this condition GST will apply on other source. For this person will share invoice with his Name not business name.
28 February 2020
Other source in your case should be other than business income.
If you are issuing invoice then the income is taxable under PGBP.So GST is applicable