Advise Angela of the following situation based upon legal principles in contract law:

She goes to City Super in IFC, Central intending to buy groceries. She fills up her basket with groceries. On approaching the cashier,Angela receives a phone call from her secretary, who tells her that her boss calls for an urgent meeting.Angela puts down the basket and wants to leave. However, the cashier insists that she must buy the products after picking them up and placing them in her basket.