This guide is applicable for both Apple and Android devices. This example is using Safari on an iPhone but will look identical when done on an Android device. 

​Step 1 - Open a web browser of your choice. If you're on an iPhone, look for Safari. If you're on Android, look for Google Chrome. Once opened, navigate to portal.office.com - Type in your email address.
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Step 2 - Type in your email along with your existing password and tap sign-in.

Step 3 - Type in your email address, existing password, and your new password twice, then tap submit. 

Step 4 - Type in your email with your new password, then tap sign-in.

Step 5 - You may be greeted by a screen asking for more information, if so, click the next button and follow on. 

Step 6 - Set up one of the options for a phone number or email address as secondary means of access.

Step 7 - This is what setting up a secondary phone looks like. Choose the desired country code, then type in the desired phone number with area code. 

Step 8 - If it's asking to keep you signed in, you've done well and are almost done. Click the yes or no button depending on your location. Your password is now reset and ready to use.