Has anyone had the problem of ‘ front assist unavailable’?

it only occurs occasionally and seems to correct itself after a few minutes.

I've had it in bad weather.

Echoing what john999boy said, I've also had it during bad weather, that is when it was really cold and when it snowed. It does go away after a while, just make sure the front radar area on the grill is clear and clean.

Also when going up / down spiral ramps in car parks for some reason.

Generally it's a dirty sensor cover though

I get it all the time. Need to take it back to the stealer to get them to sort it out as the beeping is driving me insane. 

Clean the front grill is the first thing to try.

 

after that it may need fault codes checking as there may be a hidden issue

I've had that warning when it's snowing, but last year it came on in the middle of summer and stayed on until I took it to the dealer to get it sorted out.  It turned out to be a broken bracket behind the sensor.  I've no idea how it was broken as there's no sign of damage on the sensor or the surrounding area.

Thanks for all the replies. Mine came on in heavy rain but once on a clear day too.

Anyway the problem hasn't occurred again recently so will just get them to look at it when it is next serviced.