Maybe the problem is talking, not language. It is for me. I'm not so bad at talking, also lifetime training in masking. But my issue is that I can't multitask thinking what I want to say, and making sounds at the same time. Most people are surprised I have an issue because I do talk quite OK... in a way. I use thousand filler words and I never say anything sane, but people are good at piecing it together.

Talking for me is like when my mom knits and watches TV at the same time. It shouldn't be possible.

I can think and type at the same time, because I can multitask that one well. I can even listen in on what someone says, at the same time as I type to someone else something completely different. People say that it's not doable.

I guess it just varies in what we can multitask and not.

The OP might have a totally different reason why they cannot talk well, but at least I told you about my reason.