Consumer Law, Warranties Validate signed invoice

[xabialonso]

Dear all,

I wish to know if i validate an invoice by signing it? I received an invoice today and was asked to sign it to acknowledge i've received it.Even though i did not agree with the contents and fees, I signed and dated it without writing "Received:", will this get me into trouble?? Can i still contest the fees payable for the services rendered? Really appreciate if someone could help me out!! Thanks