Remote password not working

Techwoman

I'm a longtime TeamViewer user, remotely supporting hundreds of clients. I've not had this problem before. I'm sure client is reading me out password correctly, and I'm typing it correctly, but it's not being accepted. I had him get a new password, same result. I restarted my computer (Win11). Same result. I had him restart his computer (Mac), same result. I tested my keyboard by typing in another window, same result. Any ideas?