Hi CPCM,
We appreciate your question about the maintenance of the wall oven.
The wall oven is not equipped with a self-cleaning feature nor with a steam-cleaning feature. Please refer to pages 31 - 34 of this model's user manual I have shared below for steps in maintaining your appliance.
https://downloadcenter.samsung.com/content/UM/202008/20200820093031326/NV31T4551SS_AA_DG68_01265A_00_EN_MES_CFR.pdf
Should you need more assistance, please feel free to get back to us via the following options:
1. Facebook Messenger: http://m.me/samsungsupport
2. Twitter: https://twitter.com/messages/compose?recipient_id=18768513
3. Samsung Community: https://us.community.samsung.com/t5/Samsung-Community/ct-p/us
When you message us, provide them this number 1144948769 and it will help our team pull up your information.
Leo