Can you confirm the following
Before issuing a bulk erase command are you giving the WREN opcode, and after issuing the Bulk Erase instruction are you pulling the CS high.
Can you also poll the WIP bit and tell what value it shows. The WIP bit will indicate a 1 when the erase cycle is in progress and a 0 when the erase cycle has been completed.
A BE command can be executed only when the Block Protection (BP2, BP1, BP0) bits are set to 0’s. If the BP bits are not zero, the BE command is not executed and E_ERR is not set. The BE command will skip any sectors protected by the DYB or PPB and the E_ERR status will not be set. Can you check before issuing this command that what is the status of BP bits and DYB and PPB bits.
Also can you let us know how many devices are failing. Are some devices failing or all are failing or some are passing.
Thanks and Regards,