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Yes, it looks as if your output is killed.

Are you sure the amplifier is healthy? Polarity correct, etc?

Is the VCO loop closed per se, such that it actually strives towards it target value?

Is the slew-rate in par with your simulation times?

You can try with an ideal amplifier and/or inserting an initial value at X (actually better to put initial condition on your output capacitor(s)). That will immediately tell you if the amplifer misbehaves.