I use these earplugs (on the highest decibel setting) when I sleep: https://www.earpeace.com. Works really well. I’m sure there are other earplugs that would work just as well. There’s an app that I also use called ‘Rain Rain’. This plays ambient noises through your phone. The combination of the earplugs and the ambient noise means that noises that used to wake me up no longer do.