If you are using a shared computer or device to watch YouTube videos, make sure you're logged on to your Google account, so the recommendation algorithm loads your own viewing history.
If you are logged in to your Google account, you may want to review your YouTube viewing history, either completely disabling it or deleting records of any videos you (or somebody else, inadvertently logged into your account) might have watched in the the past on the topics you don't want to see in your recommendations.
The YouTube viewing history, is an important signal to the recommendation algorithm that "follows you" throughout the different devices you may use while using YouTube.
All too frequently, one forgets to log off, especially on a family shared computer and it is a common occurrence that someone in your household uses the same device to watch YouTube without logging you out, thus skewing the statistics the algorithm uses to predict the channels you might be interested in.
To either disable or review your YouTube Watching history,
log in to your Google account at https://accounts.google.com
Under Personal info & privacy, click on activity controls
Scroll down to the bottom and you will see options to disable and review your YouTube search and watch history.
You can disable those signals by switching them off, you will get, then recommendations that rely more on your current session and location, however my advice is to review the history, where you can delete any records of any searches and watched videos that may be skewing your statistics.
Hope this helps.