Motion alert but then shows 'No video found'

Usually quite tech savvy but this has me stumped and annoyed. Had the ring doorbell 3 and chime pro for just over a year. But I'm now not getting motion notifications even if someone is right at my door. I'm getting notifications of they ring and live view is fine. Then when I'm checking the history in the evening i have plenty of motions on my property but when clicked to view i get the 'no video found' message or on the ones that do play it is just black screen. I've followed all the instructions on the site and nothing has worked. My Internet speed test using both rings recommended site and one i normally use show as being well over recommended speeds, the Wi-Fi showing as good on device health section (between 45 and 55) and the health of my ring doorbell is showing as overall good. I've tried resetting internet connection to both chime and doorbell but to no avail. Which is annoying since I'm paying £8 each month and have purchased chime pro to help with any Wi-Fi issues my doorbell might have, this was all done to ensure that I can catch the vandal teens who keep coming onto mine and my neighbours property. Anybody got any other tips that might help before i go into the queue for technical (who will no doubt tell me to do everything I've already done again)