Try your bank's debit card? Most major banks block direct crypto exchange purchases when using their credit cards however many banks do permit their debit cards to be used to buy crypto as naturally the card is linked to your bank account. Check with your bank on that.
CashApp works well if you first buy USD with your linked debit card which goes into the USD wallet. From there buy your coin using the USD wallet and the purchase usually is instant and coin goes into the BTC wallet. The buy limit with CashApp is about 1K per day from what I learned.
