Hi Sara,
You can try these options for creating the fixed asset.
Option 1
Go to Fixed Assets work center
Under Common Tasks > select New fixed asset and create, once you create it, it will be in the status 'In-process'.
Navigate to "fixed Assets" view and you will see the fixed asset with 'in-process' status
Select the fixed asset line > manual posting > Acquisition.
Fill the required and post the 'manual posting - acquisition', if the posting is successful then a fixed asset will be created
Option 2
You can post a supplier invoice with the account assignment as 'Individual material' and once the invoice is posted it will create a fixed asset automatically provided if the invoice value is morethan the value maintained under activity 'Capitalization Threshold for Fixed Assets'
Also refer to help document 'Asset Procurement in Purchasing'
Option 3
You can Migrate the Fixed Asset
Thanks
Lokesh Sharma