Infotainment screen locked without any way to access reset. Attempted to restart vehicle several times while traveling home. Nothing worked until I was able to stop vehicle, get out and let sit for a bout 5 - 10 minutes. I restarted and this error has not reoccurred. Vehicle is 3 weeks new and have had more problems in those 3 weeks than my 16-year-old GMC Sierra DRW. I feel this is a software issue that may become intermittent without any resolution. I also contacted Onstar and discovered their technical advisors are only available until 10pm Eastern....Would hate to have an issue on the West coast and find out none is available after 7pm out there.