even after i difuse the bomb, as soon as it takes of it still explodes. is this a glich or do i need to do something more?

you need to go directly to the monorail after gaining the codes. If you have and it still explodes, then you should read one of the many other threads discussing this.

i did go right there, got on the monorail and diffused the bomb with the deactivation code, i got the reply that the bomb was difused but it doesn't update to speak with hsu.