B737 flight crew reported leading edge flap malfunction. Flight crew followed checklist and landed uneventfully.

Narrative

During cruise at 37000 beginning the ZZZZX star to ZZZ; we encountered LE flaps transit light along with leading edge flap panel 1 light on overhead panel. Went to leading edge flaps transit checklist. We slowed aircraft to 260kt and ran the checklist. Requested from ATC to descend to 17000 to continue checklist to lower flaps. Requested priority handling with ATC and passed all relevant information. At below 20000 on way to 17000 we lowered flaps to 1. Everything was normal until we retracted the flaps. The indications all came back. Captain began delegating while he spoke to Dispatch and Maintenance Control. We decided to land on XXL using ILS. We followed the checklist and landed flaps 15 with autobrakes 3. Captain spoke to (FA's) flight attendants and pax of situation. The Captain landed uneventfully and we taxied ourselves to the gate. Fire truck was called to oversee any tire/brake issues and they followed us to the gate. We parked the plane and finished our remaining checklists.