Two sigils for Targaryen in the series? What is the correct one?

[lime]

I have noticed that the sigil (aka logo) of House Targaryen is different in various scenes.
This logo

is seen in these scenes:

and on the armour of Ser Arthur Dayne+

Yet this sigil

Notice here the tails has 3 circles (not two) and the dragon has arms.

This one can be seen on the clothes of Rhaegar

and on Danny's ships

Bot logos are seen in the series, are both official logos for the Targaryens?

 

[Dr.]

Perhaps, in consultation with marketing experts, they decided to rebrand.