Please check if this situation like:
PPP > Active Connections → No connected client
IP > IPSec > Policies → You see still connection from that client who is not connected and this is dynamic entry who cannot be remove
WorkARound:
CLI: /ip ipsec proposal enable YourProporsalName ;
WinBox: select your proporsal and click Enable button.
You can check my way of analyze that problem and script who detect that and do a re-enable proporsal and send me a e-mail with notification what exac client have that problem.
[WorkARound] IPSec PH2 “ready to send” without Active Peer, User cannot connect, Win10 #809 or #0 [SOLVED]
For now I wait for post like this to check if other ppl have that problem.