I'm from Philippines too and also a user of coins.ph bitcoin wallet. Aside from the big difference on buy and sell price, I'll add that you can't do buy and sell orders. So if you want to do trading using their platform you have to focus on it 24/7. Unlike on exchange you can do those orders and sell some stop loss. It is really not suggested to use that platform to trade. There are reports that when you have high amounts of bitcoin stored there the company will suddenly lock your account without any reasons. And reaching with them is difficult.
tier exchangers internationally.Its just normal for an exchange to set out KYC or verifications if there's something unusual
with your transactions.