Please check the following:

• Filter should be set on a source channel.
• Filters are sensitive to case.

If words come together in a filter, for example “one two three”, they should also come together in a message – “one two three” – to be matched.
Also remember that unsubscribing from a channel will delete all your filters so use disabling.

If you have a paid account you can use an explanation feature. Activate it by the command /settingchannel … explain on

You will start receiving explanations about filters matching on the messages.