For Jains, “Dugar” itself is a gotra.

• In the Oswal Jain community of Rajasthan, Dugar (also written Duggar, Dugad, Dugad) is a well‑known Oswal gotra.
• Many families then use this gotra name as their surname, so “surname Dugar” usually means gotra = Dugar.
• This is a community / family tradition, not something defined in Jain scriptures. Jain āgams don’t prescribe gotras; they focus on soul, karma and conduct. Gotra names like Oswal, Dugar, Surana, etc. are mainly social identifiers.

So, if your family is Oswal Jain and your surname is Dugar, your traditional clan gotra is almost certainly Dugar.

For more on Dugar / Duggar in Jain context you can read here