One of the specified coordinators is unreachable

We are using foundationdb of version 6.3.24(compiled from branch release-6.3).
The error message is shown in fdbcli when we want to change the coordinators:

fdb> coordinators 172.22.131.32:4500 172.22.131.31:4501 172.22.131.30:4502

WARNING: Long delay (Ctrl-C to interrupt)
ERROR: One of the specified coordinators is unreachable

We check the accessible of all files (even by chmod 777 -R ${fdb-install-home}), and the status details shows that all the ss is reachable, so now we are totally confused about the error message and Do not know the reason.

The environment is shown below:
3 machines of ip from 172.22.131.30-32
Each machine has 22 ss.

the status json is too large to upload

if any infomation is needed, please tell us to provide