Why are the purchased shares not visible in the holdings?

The purchased shares are short-delivered.

Ideally, when the shares are purchased, they are delivered on T+1 day. 

Now, if the shares are short-delivered, it means that the seller of the shares defaulted on the settlement of shares. In such cases, the exchange holds an auction for the same quantity of shares and delivers it to the buyer. In such cases, TradeJini notifies the clients via SMS and email. 

A Trade to Trade (T2T) stock is sold from the holdings.

Trade-to-trade stocks are not allowed to be traded intraday or BTST. If a T2T stock is sold from the holdings and bought back on the same day, then the stock won’t be visible in the holdings until it is settled i.e. on T+1.