What the statuses mean to the buyer
Pending means you have it and have not acted. Confirmed and processing mean you are packing. Shipped means it left, and with a carrier and tracking number attached the buyer gets that in Telegram. Delivered closes it.
The buyer does not read the word. They read the message it sends them, which is why the timing matters more than the label.
Cancelling does four things, not one
It flips the status, returns the items to stock, releases a gift card reserve if one was held, and reverses loyalty points the order earned. An unpaid order also stops being payable, so it cannot be resurrected from an old link.
That bundle is why cancelling twice is guarded: the compensating effects run exactly once, or stock would be returned twice and a gift card could be spent again.
Shipped finalises what cancel releases
Marking shipped closes out a reserved gift card, which is the opposite move. Getting these two the wrong way round is how a card ends up spendable after the goods are gone.
Why you should not edit statuses sideways
Setting a status directly, outside the normal flow, skips every effect above. That is how an order ends up cancelled with its stock never returned, which you then find weeks later as a count that does not match the shelf.
What to actually do
Move the order when the thing really happened, not in advance. Add the carrier and tracking when the parcel leaves, because that is the message the buyer is waiting for. The orders list also shows whether an order was paid online. More on the shop at Telegram Mini App store, and plan limits on Pricing.