You always need to create new Azure subscriptions on EA Portal if you have own EA contract to utilize Microsoft Azure. I have already posted an article how to get started with EA Portal like below.
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It's mandatory to create your Azure subscriptions on EA Portal to charge from your monetary commitment of your EA contract. Refer to an article below which roles on EA Portal can create new Azure subscriptions.
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But some folks can't find new Azure subscriptions on Azure Portal. Confirm topics below if you can't find new your subscriptions on Azure Portal.
- Enable check of Global subscription filter for your new Azure subscription
- Change Azure AD tenant associated with your new Azure subscription
How to create new subscriptions on EA Portal
Before describing the topics, you need to learn again how to create new subscriptions on EA Portal. Note that it's mandatory to have Account Owner role into your account like below.
You can lunch new tab from EA Portal to create new subscription by clicking "Add Subscription" button and redirect into new page like below. Choose "Microsoft Azure Enterprise" to charge from your EA contract.
Check two agreement terms and click "Sign up" to complete new Azure subscription.
You will be redirected into Azure Portal like below after finishing to create the subscription but you might be not possible to find new subscription like below.
Enable check of Global subscription filter for your new Azure subscription
Azure Portal offers "Global subscription filter" to make visible only selected subscriptions, but the new subscriptions are unchecked to visible as default.
Enable the new subscription on Global subscription filter by following like below.
Change Azure AD tenant associated with your new Azure subscription
I believe as you know, all Azure subscriptions are associated into an Azure Active Directory tenant and have one or more subscription owners like below. In addition that, we can't list subscriptions across Azure Active Directory tenants. 
This should be the cause why you can't find new Azure subscriptions even you have already enabled Global subscription filter.
New Azure subscriptions should be associated into an Azure Active Directory tenant which has your School or Work Account. It depends situations if your account is Microsoft Account. Refer to an article below if you are unfamiliar with School or Work Account and Microsoft Account.
docs.microsoft.com
Go to the new Azure subscription and choose "Change directory" like below.
Note you need to contact Azure Active Directory tenant administrator not EA Portal administrator if you can't move the subscription into proper Azure Active Directory tenant.
