When baking a normal map, connection lines appear on the model. I tried different solutions to the problem (with the eyes of a beginner). It seems that the problem is in the connection lines, which are taken from the "paint offset" tab.
When baking a normal map, the lines are not particularly visible, but when baking ao, they directly start to show strongly.
I specially made a scan of only one part of the pistol so that it could be better seen