I believe your problem is the V2 floating power supply. Common IC circuits typically don't operate properly with ungrounded supplies. The AD633 is rated to operate with separate plus and minus 15V (grounded) supplies but you should be able to operate from your single 24V grounded supply if you ground the VS- input, apply the 24V to the VS+ input, and the multiplier X & Y inputs stay within the limits of +4V to +20V.
Edit: The Z input also needs to be within +4V to +20V, which can be generated with a voltage divider. The Z voltage determines the DC output level of the multiplier.