Had my first oil change at Kia dealer at 5000 miles. 5W-20 oil was used. After 2000 miles I noticed owners manual required 0W-20 synthetic oil. Retuned to dealer and changed oil again to required 0W-20. The oil filler cap on recall has 5W-20 printed on it and a new cap with 0W-20 has been ordered. Any engine or warranty issues to deal with? I am back to higher miles per gallon.