Cannot find the target board

Hi, I’m new to the forum!

As you may already know by my question, I don’t have much background in programming.

I’m currently working with the latest version of Mbed studio and Nucleo F767ZI for the board. The problem is, I can’t get Mbed Studio to find my board. Everything works fine when I start my PC for the first time. But after I disconnect the board and try to reconnect, the board would not show up on the “Target” selection. The PC recognizes the board as an external drive, Mbed Studio prompts that the board is detected and I get this message “Intellisense will not update until a target is selected”. Things happen differently time to time, but none of them work.

Any advice would be greatly appreciated!