It's probably just the pilot light. Seriously, you don't want to pay for a service call until you check it. Either check the documentation that came with the stove ( you did keep all f that right ) or get the information online as to where your pilot is.

My gas stove is not lighting up on its own suddenly . I can light a flame with a lighter but it does not come on automatically . Tried everything . Whom do I call to take a look? TIA