New Seagate 1TB Solid State Hybrid Drive SATA 6Gbps 64MB doesn't work with 2011 Macbook pro 13? only as an external driver. Why?

Hello! I tried to upgrade Macbook Pro 13 with Seagate 1TB Solid State Hybrid Drive SATA 6Gbps 64MB Cache 2.5-Inch ST1000LM014. Made a full copy from old 320GB. Worked successfully for several days, but then mac failed to boot from Seagate 1TB Solid State Hybrid Drive. Right know I can only work with Seagate 1TB Solid State Hybrid Drive as an external macdrive via USB connection. So Macbook with Seagate 1TB Solid State Hybrid Drive installed internally doesn't work. When Seagate 1TB Solid State Hybrid Drive connected via usb externally Macbook works well. Macbook works with old 320 HDD installed internally very well.

What could be the problem?

Thank you!BR