Why are all my temple dates missing when they were completed many years ago?
If you are seeing multiple missing dates with the comment that they can be reserved and completed, then most likely there are duplicates in Family Tree you have not found yet and you just need to keep searching.
If you are seeing the comment "Ordinances Unavailable, contact FamilySearch..." then there are data issues on the records that support will need to fix. You will have to wait for them to contact you in regards to this post or post a few of the ID numbers for them to take a look at.
@njbmartin @Gordon Collett
I have also had this happen. Sometimes temple ordinances can 'disappear' with merges, if not done correctly. If this was the case and if it was done a while ago, unfortunately it may not be possible to track the merge via 'Recent Changes'. If you completed the work and happen to still have the temple card showing the completion date and location, you can contact FamilySearch and they will assist you.
If you didn't complete the work yourself but you have recorded the temple work via matching the FS record with a linked database such as RootsMagic etc this is not enough for FS to change the record, as has been my experience. It can be incredibly disappointing.
I hope you can resolve this.
A private message is being sent to the guest requesting additional information.