In the realm of 3D single object tracking (SOT), Siamese network-based algorithms have shown remarkable performance. However, they can lose track of targets in complex environments. To enhance tracking accuracy and continuity, in this paper we introduce a new re-detection mechanism with a dynamic anchor relocation strategy. This mechanism includes: (i) dynamic anchor generation: When tracking fails, dynamic anchors are generated and adjusted until the target is re-detected. The most confident anchor prediction becomes the tracking result; (ii) model aggregation: A re-detected module is integrated into the PTT-Net framework, significantly improving tracking accuracy compared to other algorithms; (iii) reliability assessment: An assessment criterion for tracking reliability in PTT-Net is established to balance accuracy and speed.