After enabling inline-services with flex-flow-sizing:

set chassis fpc 0 inline-services flex-flow-sizing

The following memory errors appeared on FPC shell:

[Mar 19 11:18:40.834 LOG: Err] jnh_alloc_physmem(15383): PFE 1 PhysMem Bulk DMEM, failed to allocate 0x08000100 DW.
[Mar 19 11:18:40.834 LOG: Err] jnh_hash_table_resources_allocate(2649): Failed to alloc REC 0x08000020 DW - 0x1000004 Entries @ 134217760 DW/Entry.
[Mar 19 11:18:40.834 LOG: Err] jnh_hash_pfe_create(3254): Failed hash table resources alloc for V4 Flows on PFE 1.
[Mar 19 11:18:40.834 LOG: Info] Error from jnh_hash_pfe_create for hashp 0xe64b5238.
[Mar 19 11:18:40.834 LOG: Err] jnh_free_physmem_helper(16296): No PFE 1 Bulk DMEM Physmem for 0x00000000 @ 0x499d7000.
[Mar 19 11:18:40.834 LOG: Err] jnh_free_physmem(16482): HASH jnh_app 0x004300a0 Bulk DMEM PhysMem: No match for 0x0 DW @ 0x499d7000
[Mar 19 11:18:40.834 LOG: Err] FREE ERR HASH[1]: HASH DMEM Sideband, 0 dw (0 blk) @ PA 0x499d7000 addr 0x499d7000
Traceback:
[Mar 19 11:18:40.834 LOG: Err] Frame 1: sp = 0x00000000, pc = 0x990c66a
[Mar 19 11:18:40.834 LOG: Err] Frame 2: sp = 0x00000000, pc = 0x98e9206
[Mar 19 11:18:40.834 LOG: Err] Frame 3: sp = 0x00000000, pc = 0x97345fa
[Mar 19 11:18:40.834 LOG: Err] Frame 4: sp = 0x00000000, pc = 0x9736a12
[Mar 19 11:18:40.834 LOG: Err] Frame 5: sp = 0x00000000, pc = 0x9737861
[Mar 19 11:18:40.834 LOG: Err] Frame 6: sp = 0x00000000, pc = 0x9727e3f
[Mar 19 11:18:40.834 LOG: Err] Frame 7: sp = 0x00000000, pc = 0x818c7e6
[Mar 19 11:18:40.834 LOG: Err] Frame 8: sp = 0x00000000, pc = 0xa6a8898
[Mar 19 11:18:40.834 LOG: Err] Frame 9: sp = 0x00000000, pc = 0x818c7e6
[Mar 19 11:18:40.834 LOG: Err] Frame 10: sp = 0x00000000, pc = 0xa6aa42c
[Mar 19 11:18:40.834 LOG: Err] Frame 11: sp = 0x00000000, pc = 0xa6b0bc5
[Mar 19 11:18:40.834 LOG: Err] Frame 12: sp = 0x00000000, pc = 0x807ec8d
[Mar 19 11:18:40.834 LOG: Err] Frame 13: sp = 0x00000000, pc = 0xf73881a6
[Mar 19 11:18:40.834 LOG: Err] jnh_services_flow_table_init(1343): jnh_hash_pfe_create failed
[Mar 19 11:18:40.834 LOG: Err] jnh_services_jflow_table_cfg_event(1055): Disabling inline jflow service due to internal error
[Mar 19 11:18:40.879 LOG: Err] jnh_alloc_physmem(15383): PFE 0 PhysMem Bulk DMEM, failed to allocate 0x08000100 DW.
[Mar 19 11:18:40.879 LOG: Err] jnh_hash_table_resources_allocate(2649): Failed to alloc REC 0x08000020 DW - 0x1000004 Entries @ 134217760 DW/Entry.
[Mar 19 11:18:40.879 LOG: Err] jnh_hash_pfe_create(3254): Failed hash table resources alloc for V4 Flows on PFE 0.
[Mar 19 11:18:40.879 LOG: Info] Error from jnh_hash_pfe_create for hashp 0xe64b5238.
[Mar 19 11:18:40.879 LOG: Err] jnh_free_physmem_helper(16296): No PFE 0 Bulk DMEM Physmem for 0x00000000 @ 0x499d7000.
[Mar 19 11:18:40.879 LOG: Err] jnh_free_physmem(16482): HASH jnh_app 0x004300a0 Bulk DMEM PhysMem: No match for 0x0 DW @ 0x499d7000
[Mar 19 11:18:40.879 LOG: Err] FREE ERR HASH[0]: HASH DMEM Sideband, 0 dw (0 blk) @ PA 0x499d7000 addr 0x499d7000
Traceback:
[Mar 19 11:18:40.879 LOG: Err] Frame 1: sp = 0x00000000, pc = 0x990c66a
[Mar 19 11:18:40.879 LOG: Err] Frame 2: sp = 0x00000000, pc = 0x98e9206
[Mar 19 11:18:40.879 LOG: Err] Frame 3: sp = 0x00000000, pc = 0x97345fa
[Mar 19 11:18:40.879 LOG: Err] Frame 4: sp = 0x00000000, pc = 0x9736a12
[Mar 19 11:18:40.879 LOG: Err] Frame 5: sp = 0x00000000, pc = 0x9737861
[Mar 19 11:18:40.879 LOG: Err] Frame 6: sp = 0x00000000, pc = 0x9727e3f
[Mar 19 11:18:40.879 LOG: Err] Frame 7: sp = 0x00000000, pc = 0x818c7e6
[Mar 19 11:18:40.879 LOG: Err] Frame 8: sp = 0x00000000, pc = 0xa6a8898
[Mar 19 11:18:40.879 LOG: Err] Frame 9: sp = 0x00000000, pc = 0x818c7e6
[Mar 19 11:18:40.879 LOG: Err] Frame 10: sp = 0x00000000, pc = 0xa6aa42c
[Mar 19 11:18:40.879 LOG: Err] Frame 11: sp = 0x00000000, pc = 0xa6b0bc5
[Mar 19 11:18:40.879 LOG: Err] Frame 12: sp = 0x00000000, pc = 0x807ec8d
[Mar 19 11:18:40.879 LOG: Err] Frame 13: sp = 0x00000000, pc = 0xf73881a6
[Mar 19 11:18:40.879 LOG: Err] jnh_services_flow_table_init(1343): jnh_hash_pfe_create failed
[Mar 19 11:18:40.879 LOG: Err] jnh_services_jflow_table_cfg_event(1055): Disabling inline jflow service due to internal error
 

And sampling did not work on the card:

user@router-re0> show services accounting flow inline-jflow fpc-slot 5

Flow information
FPC Slot: 5
Flow Packets: 0, Flow Bytes: 0
Active Flows: 0, Total Flows: 0
Flows Exported: 0, Flow Packets Exported: 0
Flows Inactive Timed Out: 0, Flows Active Timed Out: 0
Total Flow Insert Count: 0

IPv4 Flows:
IPv4 Flow Packets: 0, IPv4 Flow Bytes: 0
IPv4 Active Flows: 0, IPv4 Total Flows: 0
IPv4 Flows Exported: 0, IPv4 Flow Packets exported: 0
IPv4 Flows Inactive Timed Out: 0, IPv4 Flows Active Timed Out: 0
IPv4 Flow Insert Count: 0

IPv6 Flows:
IPv6 Flow Packets: 0, IPv6 Flow Bytes: 0
IPv6 Active Flows: 0, IPv6 Total Flows: 0
IPv6 Flows Exported: 0, IPv6 Flow Packets Exported: 0
IPv6 Flows Inactive Timed Out: 0, IPv6 Flows Active Timed Out: 0
IPv6 Flow Insert Count: 0

MPLS Flows:
MPLS Flow Packets: 0, MPLS Flow Bytes: 0
MPLS Active Flows: 0, MPLS Total Flows: 0
MPLS Flows Exported: 0, MPLS Flow Packets Exported: 0
MPLS Flows Inactive Timed Out: 0, MPLS Flows Active Timed Out: 0
MPLS Flow Insert Count: 0

The issue is due to memory fragmentation on the line card. As a result, the required amount of memory for sampling feature could not be allocated. The recommendation is to activate sampling with flex-flow-sizing on the newly booted line card to mitigate the risk of the memory fragmentation.