match derive_ldk_payment_preimage(payment_hash, &iv_bytes, &metadata_bytes, keys) {
Ok(preimage) => payment_preimage = Some(preimage),
Err(bad_preimage_bytes) => {
match derive_ldk_payment_preimage(payment_hash, &iv_bytes, &metadata_bytes, keys) {
Ok(preimage) => payment_preimage = Some(preimage),
Err(bad_preimage_bytes) => {