If you Mangal was of 7th house and 8th house , we would not cancel it. However as your Mangal is in the lagan it is not very strong. Also another thing to note is that You have Saturn in the 8th house, which gives long life to the native. When Gun milan is very good, partial mangal dosha can be ignored.
Blessings,
Navneet Khanna
strologer