DHCP relay issues in a bridged network

Topology of setup:

DHCP server is sending only DHCP NAK in response to client's DHCP request.
Thinking that the issue is related to an identical DHCP Transaction ID used in both DHCP Offers from server.

DHCP process walkthrough:

1. Client sends DHCP Discovery (broadcast) with self-generated transaction ID: 123
2. DHCP Discovery reaches DHCP server through 2 different Relay-agents (192.168.42.1 and 192.168.43.1) due to bridged networks.
3. DHCP server generates 2 different DHCP Offers with identical Transaction IDs, although both offered IP-address are from different subnets (42.0/24 and 43.0/24). Those DHCP offers are unicasted (from relay-agent) to the client.
4. Client receives both DHCP offers from vlan 114 and chooses one for a request.
5. Client broadcasts the DHCP request.
6. The DHCP request reaches the DHCP server. DHCP server sees the DHCP request with a TransactionID that is mapped to 2 different DHCP offers. The server responds with a DHCP NAK (negative acknowledgement). (Maybe DHCP server is not allowed to send DHCP ACK if a TransactionID is associated with more than one DHCP offers?)
7. DHCP has failed.