The problem
Ready to buy, still waiting for an answer
Without an assistant
Someone sees a post, asks about a size and waits. The owner is packing orders or serving at the counter, and by the time they reply, the customer has moved on. After an order, the same person writes again to ask where it is.
With an assistant
The assistant answers straight away from the shop's product list and knowledge base, and says so when something is sold out. When the customer is ready, it sends a personal link to the shop page, and the order lands in the same conversation. Payment goes to the shop's own account, and order updates arrive in the chat.