Maintaining a local orderbook/Inconsistencies with Websocket Updates

[o5mo-lj]

I'm having problems maintaining an accurate local orderbook because the websocket often does not send explicit removal messages for a given price point. By looking at the orderbook on the GUI i can see that I should have removed some price/amounts

The websocket feed often does not send an explicit removal message at a given price point. how should we reason about when to remove price points in the absence of an explicit removal message?