A nonce is a number assigned to each transaction from your wallet. Nonces must be sequential (0, 1, 2, 3...). If Transaction #2 is stuck, Transaction #3 cannot process.
If the error persists, your system files themselves may be damaged. 0xc86044d2 fixed
Proprietary industrial controller logs 0xc86044d2 when a CAN bus message is malformed. Fix: Vendor released firmware v2.3.1, patching the CAN parser. Verification: After upgrade, error code no longer appears; new code 0xc86044d3 introduced for a different condition. Conclusion: 0xc86044d2 fixed means the original malformed-frame error is resolved. A nonce is a number assigned to each