Missing Skills/Titles

Hey guys, not sure if anyone may have an answer or an idea here.

I used to play often a few years ago, and over that period, I completed a number of achievements, acquired a number of mounts, including my Tundra Mammoth and I also raised a number of skills to the max (fishing, cooking, first aid) while also raising about 40 reps to exalted and exploring all over...Oh, I was also a donator.

Then I stopped for about 3/4/5 years, I can't remember exactly.

When I logged back in a few days ago, my characters had no names so I had to rename them and then I realized that my main was missing a number of skills (cooking/fishing), mounts (Mammoth included), titles, and achievements.

Does anyone know what exactly may have caused this? If it can be fixed? Or do I just need to redo them?

Thanks.

Names got deleted due to name cleanup.
Some titles were removed from players because people didn't get them first.
Can't speak for mammoths and skills. Maybe you just remember poorly?