Here are some possibilities:
a) There is an area code or a prefix in the BLACKLIST that is causing other numbers getting blocked. Please review the numbers stored in your BLACKLIST to make sure there are no 1,2 or 3 digits that may be causing other numbers being blocked. Refer to section 8.2 in the manual to browse your BLACKLIST. If you see 1,2 or 3 digits numbers stored, simply press REMOVE while browsing to remove these numbers (or follow the step on section 10.2 to remove these numbers).
b) If the problem persists, it is also possible that there is a prefix or area code stored manually in the Blacklist that is causing other numbers getting blocked. Please follow step 5.1 in the manual to review/browse the prefixes and area codes stored. If you see any, you should remove these as these may be causing the call blocker to block other numbers. (to remove, simply press REMOVE while browsing, or follow the steps in section 10.3).
Note: If your call blocker is installed in parallel (with a splitter), you will need to plug-in a handset in order to follow steps on item 5.1 on the manual.
c) If you continue with this issue after reviewing your Blacklist numbers, area codes and prefixes, then it's time for you to reset all the memories on your call blocker as it may be corrupted. To do this, please refer to this article.
If problem persists, please contact us.