Hi @yvonnedburton
You don't reset it.
You find out what's causing it to go into limp mode and fix it and then it will be reset.
Limp mode is usually a transmission related problem. Something is causing it to enter limp mode to prevent more damage from occurring.
Is the check engine light on?
If possible get the vehicle's OBDII port scanned for any codes (transmission codes?).
If there are any there, they will help to find out what's wrong.
Some major USA retail auto parts chains will do this for free apparently e.g. AutoZone.