One MT router floods another with discovery udp requests

What is the purpose or issue? Frequency approx 2 per sec.
LTE — R1 (eth1) —> udp —> (eth1 wan) R2


Encapsulation type: Ethernet (1)

Capture Length: 342 bytes (2736 bits)
[Frame is marked: False]
[Frame is ignored: False]
[Protocols in frame: eth:ethertype:ip:udp:dhcp]
[Coloring Rule Name: UDP]
[Coloring Rule String: udp]
Ethernet II, Src: Routerbo_xx:xx:xx (xx:xx:xx:xx:xx:xx), Dst: Broadcast (ff:ff:ff:ff:ff:ff)
Destination: Broadcast (ff:ff:ff:ff:ff:ff)
Address: Broadcast (ff:ff:ff:ff:ff:ff)
… ..1. … … … … = LG bit: Locally administered address (this is NOT the factory default)
… …1 … … … … = IG bit: Group address (multicast/broadcast)
Source: Routerbo_xx:xx:xx (xx:xx:xx:xx:xx:xx)
Address: Routerbo_xx:xx:xx (xx:xx:xx:xx:xx:xx)
… ..0. … … … … = LG bit: Globally unique address (factory default)
… …0 … … … … = IG bit: Individual address (unicast)
Type: IPv4 (0x0800)
Internet Protocol Version 4, Src: 0.0.0.0, Dst: 255.255.255.255
0100 … = Version: 4
… 0101 = Header Length: 20 bytes (5)
Differentiated Services Field: 0x00 (DSCP: CS0, ECN: Not-ECT)
0000 00.. = Differentiated Services Codepoint: Default (0)
… ..00 = Explicit Congestion Notification: Not ECN-Capable Transport (0)
Total Length: 328
Identification: 0x0000 (0)
Flags: 0x00
0… … = Reserved bit: Not set
.0.. … = Don’t fragment: Not set
..0. … = More fragments: Not set
…0 0000 0000 0000 = Fragment Offset: 0
Time to Live: 16
Protocol: UDP (17)
Header Checksum: 0xa9a6 [validation disabled]
[Header checksum status: Unverified]
Source Address: 0.0.0.0
Destination Address: 255.255.255.255
User Datagram Protocol, Src Port: 68, Dst Port: 67
Source Port: 68
Destination Port: 67
Length: 308
Checksum: 0xe3b3 [unverified]
[Checksum Status: Unverified]
[Stream index: 0]
[Timestamps]

UDP payload (300 bytes)
Dynamic Host Configuration Protocol (Discover)
Message type: Boot Request (1)
Hardware type: Ethernet (0x01)
Hardware address length: 6
Hops: 0
Transaction ID: 0x5365c462
Seconds elapsed: 1
Bootp flags: 0x0000 (Unicast)
0… … … … = Broadcast flag: Unicast
.000 0000 0000 0000 = Reserved flags: 0x0000
Client IP address: 0.0.0.0
Your (client) IP address: 0.0.0.0
Next server IP address: 0.0.0.0
Relay agent IP address: 0.0.0.0
Client MAC address: Routerbo_xx:xx:xx (xx:xx:xx:xx:xx:xx)
Client hardware address padding: 00000000000000000000
Server host name not given
Boot file name not given
Magic cookie: DHCP
Option: (53) DHCP Message Type (Discover)
Length: 1
DHCP: Discover (1)
Option: (55) Parameter Request List
Length: 8
Parameter Request List Item: (1) Subnet Mask
Parameter Request List Item: (121) Classless Static Route
Parameter Request List Item: (3) Router
Parameter Request List Item: (33) Static Route
Parameter Request List Item: (6) Domain Name Server
Parameter Request List Item: (42) Network Time Protocol Servers
Parameter Request List Item: (138) CAPWAP Access Controllers
Parameter Request List Item: (43) Vendor-Specific Information
Option: (12) Host Name
Length: 8
Host Name: MikroTik
Option: (61) Client identifier
Length: 7
Hardware type: Ethernet (0x01)
Client MAC address: Routerbo_xx:xx:xx (xx:xx:xx:xx:xx:xx)
Option: (77) User Class Information
Length: 8
Instance of User Class: [0]
User Class Length: 7
User Class Data: xxxxxxxxxx
Option: (255) End
Option End: 255
Padding: 0000000000000000000000000000000000