I have seen that occur with another student. There is a bug within the Salesforce Platform. Luckily all the steps complete before Step 71 are saved, Salesforce glitched when regarding you back to the home page. You can continue by clicking "switch to lighting experience" to return to the Salesforce Platform. Just click the Setup gear and Setup next to your profile icon to continue with Step 72.
I have seen that occur with another student. There is a bug within the Salesforce Platform. Luckily all the steps complete before Step 71 are saved, Salesforce glitched when regarding you back to the home page. You can continue by clicking "switch to lighting experience" to return to the Salesforce Platform. Just click the Setup gear and Setup next to your profile icon to continue with Step 72.