I love that I can play white noise to my speaker with just a simple voice command. All of a sudden, it doesn't do it in the same way anymore. I would say "Hey Google, okay rain sounds for 1 hour". It would normally play for that time and not repeat. If I woke up in the middle of the night, I could say the same command. Now the command repeats. I don't need to have the white noise repeat all through the night and to save some life on the speaker. Is this a glitch or something like that? I've done the command on the pixel 6 pro and it works as it should.
Thanks for posting and certainly, that's not the experience we want you to have with your Nest speaker. A few questions: what Nest speaker are you using? Are you trying to play rain sound or any ambient noise through routines or a timer or just a normal "Hey, Google!" command? It would help a lot if you could do a sequential reboot first. Unplug the power cord of your router followed by your Nest speakers. Plug them back in after 3 minutes or 5 minutes tops. Restarting your phone might also help.
Also, for more information, check out MplsCustomer and MikeClark helpful responses.
Keep us posted.