We have received many reports lately that you are unable to select full wet weather tyres in stint 5 of the race.
As we are unable to work on this right away, we have taken the temporary measure of disabling wet weather conditions in the simulator. They will be restored once the strategy window is fixed. We are focused primarily on upgrading the service right now and will not be able to look at this until we are done with this update.
This temporary solution will mean that wet weather tyres are not required, so you won't be caught out by this again.