I have suffered for years with a constant ringing noise, sometimes it is very noticeable and other times less so, but it is always there. I use several apps on my phone, all night, every night, to help with getting to sleep, and staying asleep. My favourite is ReSound Relief, specifically for tinnitus, which has standard sounds and also allows you to create custom sounds by combining noises. Some end up as simply relaxing noise which, if you focus on it, can distract you from the tinnitus noise. Some, can try to actually dissipate the tinnitus noise by creating a sort of 'opposite' noise which cancels out your internal sounds. It also offers relaxation, meditation, and other advice. It sounds like nonsense but I find it very effective and I struggle to sleep without it. Apart from that, sadly treatment, such as it is, consists of learning to live with it. Good luck.