Forgeting vocabulary

how to retain vocabulary in the long term memory sometimes I forget vocabulary I learned just a few hours ago when reading and when i’m speaking to a native speaker of a language i’m learning i have to really try hard to remember is this normal and how can i get pass this?

Yes, quite normal. As a matter of fact, to be expected. Get more exposure. Just keep reading, listening, you’ll encounter the words again and again and they’ll end up becoming familiar.