It is your liability which is discharged by the forged cheques.
You never paid the money to the internet used after the same was paid by forged cheques.
Whosoever has written your name but forgery is committee to you benefit.
You are likely to confront the following questions
1. For how many years you had used the internet
2. For how many months such cheques have been used for your payment
3. How did you pay the internet provided during the period for which payment was made by cheque.
4. Has the internet provided used any receipt of this cheque.
5. Whether the said receipt is in your name.
6. What is the stand of the employee of internet provided who collected the cheque.
7. Who actually gave cheque to internet provider.
8. Who is account holder.
9. How are you related to account holder.
10. How are your relations with you.
11. Why these cheqeus are forged by someone for your benefit.
12. Howe many cheques of this book were used for IIIrd party benefit other than you.
13. Who signed the cheques.
14. When did you know about this payment.
15. Whether the signature are genuine or forged.
16. Whether the writing of the amount and beneficiary’s name in the same ink while it was signed.
17. Whether the original cheque ahs fingerprint of you or any of your family member.
18. Even if the endorsement and writing and fingerprints on the cheque is not in your (nor of family member) handwriting then why it should not be believed that you stole the cheques got endorses/ written in another hand.
19. How many payments to other service providers you have made by cheques and how many do not belong to your account.
For all these answers police will be justified to seek your remand.
Better go for amicable settlement with account holder.