Mount_root fails for /dev/mtd2 and /dev/mtd3 blocks

Hi !
I'm in need of some help;
The device boots up with the following errors; resulting in overlayfs not getting mounted.
On debugging this, found that the mtd error code returns 13 (permission denied) for these dev blocks.

[ 11.850000] mount_root: Could not open mtd device: /dev/mtd3
[ 11.860000] mount_root: reading rootfs_data failed
[ 11.860000] mount_root: Could not open mtd device: /dev/mtd2
[ 11.870000] mount_root: reading rootfs failed
[ 11.870000] mount_root: mounting /dev/root

The flash is partitioned as below:

[    1.380000] Creating 9 MTD partitions on "EN7512-SPI_NAND":
[    1.390000] 0x000000000000-0x000000080000 : "u-boot"
[    1.400000] 0x000000080000-0x0000001c6681 : "kernel"
[    1.400000] 0x0000001c6681-0x0000009b6681 : "rootfs"
[    1.410000] 0x0000006da0df-0x0000009b66cf : "rootfs_data"
[    1.410000] 0x000000c92c71-0x00000135c5ac : "art"
[    1.420000] 0x000000080000-0x0000001c66c5 : "firmware"
[    1.420000] 0x00000107ffbc-0x0000011c6681 : "kernel_slave"
[    1.430000] 0x00000107ffbc-0x00000dcf98f7 : "rootfs_slave"
[    1.440000] 0x00000de40000-0x00000e000000 : "reservearea"

Can someone please help me out with this ?