Why won't carousell seller accept LBC CoD? Could this be a scam?

Sorry, I didn't know where else to post this, I looked up online where people posted about Carousell and it lead me here. For context I'm trying to buy a coach bag for my partner for as a gift, but I'm pretty skeptical with buying from these selling apps/website where meeting up in person or motor delivery is not possible. And as the title says, the seller wants to use GCash payment, I asked if they could do LBC CoD but they declined, saying it already has assurance when paying which made me rather suspicious. Any helpful advice would be appreciated