"And yesterday she sold me a giraffe…"

Translation: Und gestern hat sie mir eine Giraffe verkauft…

[markbooth]

Is there a reason why it doesn't allow verkaufte, just hat ... verkauft or is it just because its not in the system yet?

[Raisinnoir]

Report it. "Und gestern verkaufte sie mir eine Giraffe" is right.

[dragonzkiller]

For anyone who may comes to this later, markbooth is correct. However, in German you should use the Perfekt form (hat...verkauft) over the Präteritum (verkaufte). Generally the Perfekt is used more than the Präteritum when used for perfective past (preterite).

TLDR: It's usually better to use the "haben" form for past tense over the preterite.

[WandererBo]

In spoken German you are absolutely right. But in written translation you must respect the tense.

[bkerdan]

Sie VERKAUFTE mir.... is correct.

[BaloghTams19]

Offensichtlich war sie sehr überzeugend.