Help! I cannot run a MIDCP in the second iteraton!

I formulate a mixed integer linear programing, and I have already got a CVX professional licence and the Gurobi licence, and installed both of them in matlab.
Now I use them to solve the MIDCP problem in SDP mode, after the first iterations, I have got the solution, however, the second iteration is failed. An error message is as follows:

And the matlab code is as follows:
The variables are t(m), u, r_bh_fixedC(m), and the above forms are all scalars. Why I cannot run the second iterations.
If you reading this, I really need your help.
Thank you.

And the matlab code in line 58 is as follows:

Insert the following code before that offending statement:
Now re-run, and share with us the output.

Thanks a lot, Mr.Grant!
your method really helps me find the problem, I redefined the B before the line 58, thus the error message generated.
Thanks again, very happy to have a dialogue with you!