NickW I feel your pain.
I have similar problem with the True ads which seem to not affect others

Has been happening intermittently for quite a while now
I find the only way to get around it is open another session and try again - sometimes this works and sometimes it doesnt.
Very frustrating.
Incidentally it seems we dont get the same ads at the same time (ie I can be cussing the True ads and others tell me they see some other ad) - any reason why?