question about Windows server 2003 activation?plz help ?

[newguy_feroz]

i have win server 2003 standard edition(original) OS on my pc, after some days i install the server SP2 patch and restart the system then it is asking for activation. then i uninstall the sp2 patch and again restart the system then also it is asking for activation when im trying to activate Os with telephone it is saying "our records are saying this product is already activated",and in internet activation it is asking the key i put the original key but it is not taking what i do?