How to help my dog overcome fear from other dogs ?

Hi, first of all my dog is American Staffordshire Terrier, she's a girl. she's 1.4 years old. When she was a puppy, around 3.5 months old she was so scared from everything, her self confidence was so low.

When dogs were barking, or other dogs nearby, she would freeze, her tail moved down the legs and she wont move at all, i was working with her and by the time she managed to overcome that fear.

Since then when dogs approaching she can like them and play with them and sometimes she is so scared that she tries to runaway and put her tail between the legs. When she was a puppy i was going everything i could that she won't be scared from the surrounding, was going to the sea a lot, i took her to streams and also she was meeting dogs almost all the time.

I'm clueless, not sure what to do so she won't be so scared from dogs tried everything.

Even when something scary happened to her during walking outside she won't take treats at all.

Besides she never had any past traumatic experience with dogs.

Thanks a lot!