Hi @olmichal
Don't worry. If your admin has created an environment for you. Make sure you have a System administrator or System Customiser role for that environment.
If it is enabled for you it will take 30 - 60 minutes to reflect.
If the above solution not helping you. Then try the following steps.
Pre: Use incognito window
1. https://powerapps.microsoft.com/en-nz/developerplan/
2. Choose the "Existing user? Add a dev environment"
3. Provide your org email id.
4. Choose country and click finish
5. You will get a new developer environment in your org.
Note: If your org has restricted you from creating an environment then please signup for Office 365 E5 trial or dev Then follow the above steps.
Hope it helps.
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