There exist "advanced filter settings" - I don't remember which are the defaults, but you might want to look at them:

"... Quality filter, when turned on, filters lower-quality content from your notifications, for example, duplicate Tweets or content that appears to be automated ...

In addition to enabling the quality filter, you can choose to disable notifications from the following types of accounts:

- Accounts that are new (that you don’t follow).

- Accounts that don’t follow you (that you don’t follow).

- Accounts you don’t follow.

- Accounts with a default profile photo (that you don’t follow).

- Accounts without a confirmed email address (that you don’t follow).

- Accounts without a confirmed phone number (that you don’t follow)."

https://help.twitter.com/en/managing-your-account/understand...

So many things don't work properly on Twitter. I've just embraced the dysfunctionality of it all. I look like a total jerk when I don't notice replies, but I can't afford the time it takes to click through 20 pages just to be sure that no replies are unanswered... Too much work is involved in being active on Twitter, the "reduce clicks" UI/UX movement is officially dead. :(

That happens to me and it’s so detrimental. I end up ignoring people who reach out to me.

do you have the quality filter on?

I have all the helpful "filters" disabled and still regularly miss notifications for replies - it seems like Twitter doesn't notify you when a "small" account, the ones whose replies get hidden for some AI's random reason, replies.

I didn't know there was such a filter. I'll check when Twitter comes back online.