I can't see any problem in the interrupt routines you've showed...
Maybe you are doing something wrong in the main loop..check the following:

Did you put a jump instruction at org 0000h? If you did not, the program will directly go to the interrupt routine on reset, but may not work again...

Are you affecting the TCON or TMOD or IE registers anywhere in the main program loop?

Are you clearing IE.0 anywhere else in the main loop ?

They are all simple mistakes, of course, but these are the ones that are most easily overlooked.
I cant think of any other possibility right now.. will get back to you if i can :)

Kundi