OSPF common issues,Troubleshooting Neighbor Adjacency

1-OSPF, Hello/Dead interval
R1 does not form and OSPF neighbor adjacency with R2.
Due to the hello-interval
ip ospf hello-interval 25 defined on R1
Debug message:
00:41:46: OSPF: Rcv hello from 192.168.2.2 area 0 from GigabitEthernet0/0 10.10.230.2
00:41:46: OSPF: Mismatched hello parameters from 10.10.230.2

2. OSPF Router ID
An OSPF neighbor adjacency is not formed between R3 in the main office and R6 in the Branch3 office. What is causing the problem?
The R3 router ID is configured on R6

3- OSPF area ID

An OSPF neighbor adjacency is not formed between R3 in the main office and R4 in the Branch1 office. What is causing the problem?
There is an area ID mismatch.

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