How do I rebuild the catalog on time machine backup hard drive?

My Time machine backup drive has started giving me these errors on doing a fsck. How can I rebuild the indexes on this drive? I just upgraded to Mac OS Mojave 10.14.6. The drive has 2 partitioned as: 1.9TB for time machine (HFS+) 100GB for other files (HFS+) Logs: /dev/rdisk2s2: fsck_hfs started at Sat Feb 15 08:37:39 2020 /dev/rdisk2s2: /dev/rdisk2s2: ** /dev/rdisk2s2 /dev/rdisk2s2: Executing fsck_hfs (version hfs-407.200.4). /dev/rdisk2s2: ** Checking Journaled HFS Plus volume. /dev/rdisk2s2: The volume name is 2TB /dev/rdisk2s2: ** Checking extents overflow file. /dev/rdisk2s2: ** Checking catalog file. /dev/rdisk2s2: ** Checking multi-linked files. /dev/rdisk2s2: ** Checking catalog hierarchy. /dev/rdisk2s2: ** Checking extended attributes file. /dev/rdisk2s2: ** Checking multi-linked directories. /dev/rdisk2s2: Invalid parent for directory inode (id = 11770766) /dev/rdisk2s2: (It should be 19 instead of 18) /dev/rdisk2s2: Invalid name for directory inode (id = 11770766) /dev/rdisk2s2: (It should be dir_11770766 instead of temp11770766) /dev/rdisk2s2: Incorrect number of directory hard links /dev/rdisk2s2: ** The volume 2TB could not be verified completely. /dev/rdisk2s2: fsck_hfs completed at Sat Feb 15 09:02:06 2020 On a ubuntu VM, I am seeing: $ sudo fsck.hfsplus -dfy /dev/sda2 ** /dev/sda2 Using cacheBlockSize=32K cacheTotalBlock=1024 cacheSize=32768K. ** Checking HFS Plus volume. ** Checking Extents Overflow file. ** Checking Catalog file. ** Checking multi-linked files. ** Checking Catalog hierarchy. ** Volume check failed. volume check failed with error 5 volume type is pure HFS+ primary MDB is at block 0 0x00 alternate MDB is at block 0 0x00 primary VHB is at block 2 0x02 alternate VHB is at block 3711042830 0xdd32050e sector size = 512 0x200 VolumeObject flags = 0x07 total sectors for volume = 3711042832 0xdd320510 total sectors for embedded volume = 0 0x00 I tried to rebuild the catalog using the -r option (on ubuntu) but that failed: $ sudo fsck.hfsplus -dfyr /dev/sda2 ** /dev/sda2 Using cacheBlockSize=32K cacheTotalBlock=1024 cacheSize=32768K. could not get volume block 2, err 5 could not get alternate volume header at 3711042830, err 5 unknown volume type primary MDB is at block 0 0x00 alternate MDB is at block 0 0x00 primary VHB is at block 0 0x00 alternate VHB is at block 0 0x00 sector size = 512 0x200 VolumeObject flags = 0x01 total sectors for volume = 3711042832 0xdd320510 total sectors for embedded volume = 0 0x00