1 Computer Works and the other Doesnt

Wonder if the community at large can help.

I have 2 kali linux instances running on Virtual Box and both up to date. On the challenge Script Kiddie, I can perform the exploit perfectly and recieve a reverse shell in seconds on computer A. On computer B, no chance. It sits loading and never catches a shell despite repeating the process several times and following the exact same steps. they are on the same network, and both have got their AV disabled as I have found sometime this affects shells. I have also completed challeneges on the computer not recieveing the shell before.

What are my next logical fault finding steps? As I am really stumped on how this is happening.

p.s. The computer A which works is a Dell Laptop, and the PC B that doesnt is a Desktop running on the same wifi.

Many thanks for any help I get in advance.

Maybe try giving computer B’s box more RAM,or try to reinstall virtualbox or just kali.Try to use the .iso(or .vmdk if you already use the iso) of kali when setting up the vm.