sometimes I cant type with space between words

Were the affected .AI documents created originally in Adobe Illustrator or were the .AI files generated by a rival graphics application? I've seen pretty strange things from .AI files exported by other applications. Line spacing can often be messed up and sometimes even word spacing is glitched or non-existent. Changing character and paragraph settings does little to correct the errors; the settings either under-correct or over-correct. It's as if the text objects are corrupted somehow. One approach I've found that seems to work alright: Create a new Illustrator document and then make some dummy area text and point text objects from scratch in that fresh document using the same typefaces, point sizes, etc that are in the .AI document that has the text errors. Copy those good text objects to the clipboard and paste them into the .AI document with the text errors. Select the bad pieces of text and use the eyedropper tool to copy the attributes of the good text objects. That usually fixes the problems.

Select the Text object, got  paragraph panel, from the fly out menu select " Reset paragraph"

Go to the Paragraph panel flyout menu and check the settings for word spacing in the Justification dialog.