are you able to block no caller id?
234034
no, as no number is associated with the call for it to be blocked. Not on the phone itself but most cell carriers have a feature to block these calls. Check with your cell provider and you may find that it's already a service that is part of your calling plan and they can simply enable it for you.
293166
['Launch the Phone app.', 'Tap Recents.', 'Locate the number you want to block in the All or Missed calls list.', 'Tap the information icon (the encircled lowercase "i") to the right of the number.', 'Scroll down the Caller ID screen and tap Block this Caller.']
460067
If the incoming call shows Unknown or Unknown Caller, the caller's phone or network might be set to hide or block the caller ID for all calls. ... If you have no caller ID display at all, you may need to Contact Us to check that it is on your account.
774575
["Open your Android's Settings. It's the gear. ... ", "Scroll down and tap Call Settings. It's under the “Device” header.", 'Tap Voice Call.', 'Tap Additional Settings.', 'Tap Caller ID. A pop-up will appear.', 'Tap Hide number. Your phone number is now hidden from caller ID when you make outbound calls.']
886392
['Open Contacts.', 'Select the entry for the person you want to bypass DND.', "Tap “Edit” in the card's upper right corner.", 'Scroll down to “Ringtone” and tap it.', 'At the top of the next card, toggle Emergency Bypass to “on.” That allows calls from that person to bypass Do Not Disturb.']
1205835
If the number you wish to block is not a known contact, there's another option available. Simply open the Phone app and tap Recents. From here, tap on the i icon next to the number you want to block, scroll down, and tap Block this Caller.
453046
From the phone app tap More > Call Settings > Call Rejection. Next, tap 'Auto reject list' and then toggle the 'Unknown' option to the on position and all calls from unknown numbers will be blocked.
1065427
['From a Home screen, tap the Phone app .', 'From Recents, tap the Info icon. next to the contact or number. Alternatively, tap Contacts then select the preferred contact.', 'Scroll to the bottom of the screen then tap Block this Caller. To unblock, tap Unblock this caller.', 'Tap Block Contact.']
413163
Phone. If you're in the Phone app under Recents, tap next to the phone number or contact that you want to block. Scroll to the bottom of your screen, then tap Block this Caller.
175949
Calls that show up as "No Caller ID" means that the caller has blocked their number from appearing when calling you. When it comes up as "Unknown" it normally means that the network was not able to get the information when the call was made.
189164
(By the way, when you block a person on Duo, the person won't know it. When they call, they'll just hear your line ring and ring continuously.) If Knock Knock really isn't your thing, you can disable it altogether in Duo's Settings menu.
504838
If you've installed a version of iOS 10 on your iPhone, you can block numbers without having to save them as a contact first. When you block a number, you stop receiving calls, FaceTime notifications, or texts from that number.
496802
Press VOLUME▼ until you see Call Block, then press MENU/SELECT. ... Press VOLUME▼ until you see Add new entry, then press MENU/SELECT. Enter the complete phone number of the party you wish to block, then press MENU/SELECT.
103655
It's possible to call someone even if they've blocked your number on their iPhone, because the iOS blocking feature relies on your caller ID being visible... and you can hide that fairly easily. Whether it's advisable, ethical or even legal to do so is another matter.
887591
Call your cell carrier. They can block a number for you. Tap the i next to the entry for one of their calls in the call log. Scroll down and tap block contact.
1235142
With iOS 13, you can turn on Silence Unknown Callers to avoid getting calls from people you don't know. This blocks phone numbers that you've never been in contact with and don't have saved in your contacts list. ... Calls from unknown numbers are silenced and sent to your voicemail, and appear in your recent calls list.
710984
Alternatively, you can stop your caller ID being revealed by using the relevant code for your country - 141 from a UK landline, for instance, or *67 in the US. Now you can call the blocking iPhone, and it will ring normally, since it doesn't know you're the person it blocked.