My biological mother passed away. I want to take her name through the temple but can't use family search to view her ordinances, her last ward is unknown to me.
@CrystalLee Badger1 Post your comment under the Temple Category and a MOD will help direct your issue to a team that can get your mother's DOD recorded on her membership record.
Are you pretty certain her ward clerk marked her membership record as deceased?
If you think there is a chance that did not happen - you could try having your present ward clerk - request her records and then you can have him mark them as deceased.
once a persons records are marked as deceased - at some point not too long after that you should see the record in Family Tree.