Trouble with in home display it say's 'searching for smart meter'?

@BPLightlog This is what I can see. It doesn't moving forward from here.

What about any lights flashing on your meter?

@BPLightlog there are no lights flashing on the device.

No lights flashing on your meter (not your IHD)?

@BPLightlog 

On the meter the "Mesh" light is flashing.

[Off-topic for a moment]

Woo-hoo! A working mesh meter - the first I’ve seen depicted in these forums. How exciting!

I’m not sure it is ‘working’ at the minute .. the OP suggests that the online account and IHD have not updated in 3 days

Probably connected - or not (!). I too had problems getting readings and usage data online over the weekend, so there may have been a (separate) reason for that - DCC hiccups, perhaps. Friday, Saturday and Sunday’s usage turned up this morning, but I’m still waiting for last night’s reading.

If the mesh LED is flashing and some data have been received by OVO, the meter is connected. That’s what I was getting excited about - we haven’t heard much about mesh.

It’s suggested that there has been a data lag over the last few days and that may be why your account is not up to date. 
The meter is operating locally and so should always be correct. 
Although I would have expected your IHD to be still connected unless it needs the external Mesh link to work. 
You could try disconnecting your IHD for a few minutes and then switching it back on but it may be that once the data begins to be reconnected, it will all work.