Sometimes I cant say a specific word?

Sometimes I cant say a specific word? Hello! I just wanted to see if anyone else faces this problem, and if there are anyways to overcome this. As a kid I had a stutter but underwent speech therapy, and I only stutter very rarely (if you call it that?). Sometimes I know what I want to say but I just cant say it? Like it wont come out of my mouth but I know exactly the word I want to say, especially when introducing myself. Almost 100% of the time when telling someone new my name I just cant. This makes it really difficult to meet new people and wanted to know if anyone had any insight on the issue? Thank you :)