how can i fix my veritas alarm after electric has been off too long?

hi, need some help. about 6 months ago my electric run out as i am on a metre. it has been off for about 8 hours, after which i put my electric key in to credit my account. my electric came on but all of a sudden my alarm wouldnt go off. i asked my landlord for help but he just told me to wait for the main battery to recharge itself. however it never did. so i am unable to use my alarm at all! it wont take any code and neither me nor my landlord have the manual. now everytime my electric metre clicks off, being out of credit, my alarm doesnt go off for about 2 hours and nothing i do works. i cant unset it or reset it. its driving me insane as i cant secure my house and my landlord is a nightmare! please help me as i cant afford to get anyone to look at it for me. thanks