Im using same code since but now i cannot open my digital safe is noble H0850

The batteries could be too discharged to release the bolt locking mechanism so the key must be used to gain entry to replace the batteries and possibly reset the code.

The dry batteries used in an electronic safe last such a long time they are often forgotten until trouble is experienced. Once accessed it is often discovered one or more of the batteries have leaked and caused corrosion so extensive cleaning and sometimes repairs must be carried out before long life and reliability can be assured.

It is wise to refer to the instruction booklet beforehand.

Good luck!