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Sounds like the furnace is shutting off on high limit.Do you have a meter for troubleshooting?
Causes for this are
2.Dirty blower wheel
3.Motor not moving enough air
4.Dirty ac coil if you have AC
5.Bad limit switch tripping prematurely
6.Defective heat exchanger.
Our first step is to verify limit is the issue.
If furnace has a control board there should be an error light that flashes when furnace fails.