Oi's customers can prevent the other person from discovering their number through the restricted mode, which makes it possible to make anonymous calls. Whoever receives the call ends up seeing something like "No number", "Unknown" or "Private connection". For this reason, the following tutorial shows how to bind restricted in Oi.
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The procedure was performed on an iPhone 8 with iOS 12, but the steps are the same for smartphones with Android and any other cell phone - including basic handsets.
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Learn how to make private number calls in Oi
Step 1. Open the phone application of your cell phone and type "# 31 #" (without the quotation marks). Then enter the phone number you want to call.
Local call with private number
Step 2. If you want to call collect, you can add the "9090" before the number normally. That way, the number should look like this: # 31 # 9090 99969-1234.
Local calling to collect with private number
Step 3. If it is a long-distance call, you need to enter your carrier code and area code. The number should be in this format: # 31 # 0XX 11 99969-1234. In the following example, we use the DDD of São Paulo (11).
Making a long distance call with a private number
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