Thank you for your post.
Can you kindly try to restart both side of devices and restart TeamViewer service please, then connect again to check for any difference.
If the same blockly screen happens, can you kindly provide the operating system of your devices please.
Hope the information is helpful.
Thank you for the reply.
I have created a Support Ticket for your issue. Kindly wait for our TeamViewer Support Team to contact you for a possible solution.