How do I get my Apple cash back onto my debit card

Tp transfer Apple Cash to a debit card, see instructions in: Transfer money in Apple Cash to your bank account or debit card - Apple Support

Note that transfers to a bank account are free but there is a small free for transfers to a debit card. See the following from the above support article:

footnote 2 - A 1.5 percent fee (with a minimum fee of $0.25 and a maximum fee of $15) is deducted from the amount of each Instant Transfer.

See -> Transfer money in Apple Cash to your bank account or debit card

Transfer money in Apple Cash to your bank account or debit card

How do I get my debit card attached to Apple Pay again