1y basset bitch 🐶scared of strangers. please help

My girl Rowen is 1year old. Had her since she was 8 weeks old. Shes been brouggt up with our 3 kids who she just loves. Shes gentle, loving, great pet. Around 6m of age she started acting strange out on walks. She would be startled with people walking by, minding there own. More so men than women. She tries to make herself small. Makes a whimpering noise, hair stands on end,she will keep looking back at the person til she cant see them. Sometimes she will just stand and bark and she backs away if they try to talk to her. Shes scared…
I can be walking her on my own or with kids, she is still the same. Shes great with family members when they visit. But anyone else in house she dosnt know she will back up and bark at them.
Please help