Dew line off scale

I just happened to check my website. I notice that the dew point is measuring off the scale. Is this because the autoscale feature is not working, and is it possible for me to correct this as a permanent fix so that I know that in future, all plots will be recorded on the scale.

For the example, please look at:-

i most likely do not have it working very well for the that graph
next time it happens zip and email me the file latest.inf and month62003.inf from the folder dtafiles