Why hasn't my refund from Apple appeared on my bank account?

See: Check the status of a refund for apps or content that you bought from Apple - Apple Support

Depending on how you made the initial payment, the refund will go to that same payment method, but will vary on how long that can take (after approval):

• Store credit—It might take up to 48 hours to see the refund in your Apple Account balance.
• Mobile phone billing—It might take up to 60 days for the statement to show the refund. Processing time might be affected by your carrier. You can contact your carrier for an update.
• Credit and debit cards, Apple Pay, Apple Cash, and all other payment methods—It might take up to 30 days for the statement to show the refund. If you don't see the refund after 30 days, contact your financial institution.

• Kredi ve banka kartları, Apple Pay, Apple Cash ve diğer tüm ödeme yöntemleri — Ekstrede geri ödemenin görünmesi 30 güne kadar sürebilir. 30 gün sonra geri ödemeyi görmüyorsanız, finans kuruluşunuzla iletişime geçin.

I also requested refund for apple arcade on my mac. It shows refunded but the money isn’t in after 4 months.