First you will simply open the Edge app.
Viewing the list of wallets, find the wallet you want the Seed Phrase of, then tap on the wallet.
Tap on the gear icon located at the upper right.
The following should appear:
Here, you will simply tap on. 'Master Private Key' The following should appear:
Enter the password of your account and then the Seed Phrase / Master Private Key will appear.
DO NOT SHARE THE SEED PHRASE WITH ANYONE.
SHARING THIS INFORMATION WILL COMPROMISE THE SECURITY OF YOUR ACCOUNT AND YOUR FUNDS INSIDE THE WALLET.
FUNDS INSIDE THE WALLET WILL BE IN DANGER OF BEING STOLEN BY ANYONE WHO VIEWS YOUR SEED PHRASE.