taproot – “non-mandatory-script-verify-flag (Invalid Schnorr signature)” error despite successful Schnorr signature verification?

I am working on verifying a Schnorr signature for a Bitcoin transaction, and despite the signature verification succeeding, I’m encountering the following error when broadcasting the transaction:

Status Err("RPC error: Object {\"code\": Number(-26), \"message\": String(\"non-mandatory-script-verify-flag (Invalid Schnorr signature)\")}")

Here are the details of my transaction:

Unsigned Transaction Hex:

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

Signed Transaction Hex:

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

I’ve verified the Schnorr signature using the appropriate sighash, and everything checks out. Yet, when I try to broadcast the transaction, I receive the above RPC error.

What could be causing this error, and how can I resolve it?

Additional Context:

• I’m working with SegWit v1 Taproot outputs.
• The signature verification process uses the correct sighash.
• The nLockTime and nSequence fields are properly set.

Any insights or suggestions would be greatly appreciated!

Code to verify signature

let sk = SecretKey::from_str("8756415bbbbf1ce134ca7b97e2ca584cb52150783cb37f78cc41ccc7aacc10f1").unwrap();

let secp = Secp256k1::new();
let hex_msg = "0b5d2c9103c794eec24dd3dbbbfc8c8efc377d3fd613b958bdfc9d649166dc5f";
let msg = bdk::bitcoin::secp256k1::Message::from_slice(&hex::decode(hex_msg).unwrap()).unwrap();
let sig = bdk::bitcoin::secp256k1::schnorr::Signature::from_slice(&hex::decode("b9ca544040e9dee3b547b5c781ae13d15a5b20369e522b684c240a9e353b9b4bde1bca69642963801b33dd8ecc50c8714cfa4bb386390a867baabafde59dfd30").unwrap()).unwrap();

let pubkey = bdk::bitcoin::key::PublicKey::from_str("020ea2746ae09dfcd1bfbf0f1bc819f7d1192c8fefd65d4ce3a0f510737a18d61a").unwrap();

println!("Status {}", secp.verify_schnorr(&sig, &msg, &pubkey.to_x_only_pubkey()).is_ok());