1. My first dozen times were awkward. After weeks of practice, I became enjoy having sex with the doll. I would recommend you warm her up with the USB stick and you will like that. It is a good idea to attach some persona, fantasy or voice. She’ll sometimes be someone you knew or someone you make up. Re-enacting a favourite porn storyline is a good place to start. Don’t give up. It’s a lot of fun when you are smooth sailing.
2. Eye contact is a large part of intimate moments. If you look into fake-looking eyes, it might be creating a subconscious negative trigger that results in the loss of desire/performance. So lasting longer in doggy position would mean a less likely chance of that trigger being activated because your eyes are less likely to register anything in view as fake.
3. Maybe its because she isn’t real to you. Get to know her better. Underneath the TPE is a personality that needs to be freed. The more you free her, the more real she will become. Then the way your body reacts to her will change.