Hello. I am having the same problem. I just discovered my node had been offline for over a month, and realized I needed to update wallet.
When I enter my wallet now (it is v0.12.5.1) my node says missing, and I successfully restart it.
Next time I come to check it, it is offline again.
When I use crown-cli getinfo, I get this info:
"version" : 120401,
"protocolversion" : 70052,
"walletversion" : 61000,
"balance" : 0.00000000,
"blocks" : 1987739,
crown-cli systemnode status says Systemnode successfully started
Can you please help with this issue?