Unexpected output from DSolve

why DSolve can’t solve this ODE?
I put f^[Beta][[Xi]] in DSolve, it doesn’t solve it at all.

DSolve provided the solution.We can check whether the solution given by DSolve is correct:

Regards M.I

Thank you

Actually, I want to solve the equation in the handwritten image. I took it out of the complex form by changing the variable and made it the last line, and then I wrote the code that is in the next image, but I could not apply the variable change and the rest of the conditions in the next image from the beginning. Can you help me in this regard?

That’s all I got:

Yes, I think so. But unfortunately the code fails when run on my system. Maybe it’s because of the version?

Code from here:

Thanks for your hard work on this.

Many thanks.