Let me offer some things to check/adjust which may help:
- First thing to check is the Character Styles panel, to make sure that its set to [None]. Even the most experienced InDesign users can find themselves caught up in unexpected and otherwise unexplainable text issues because an odd character style somehow was applied without anyone noticing.
- Next, close all InDesign documents, but leave InDesign itself open on your screen. Go to the Paragraph Styles panel, double-click on the [Basic Paragraph] style and confirm, going through each of the settings listed in the list box at the left of the Paragraph Style Options dialog box are set exactly the way you want them to be. Once everything everything is set the way you want, click the OK button so set your preferences for your [Basic Paragraph] style.
- Create a new document. Get your text tool and type a line of type. Check your Control Panel to see if the type you just created actually matches the settings you want that type to have. If it's not, then check your Paragraph Styles panel to make sure that [Basic Paragraph} is selected, and that there is no + sign indicating that the type you just laid down is different because it's "based on" the style, but somehow changed and different.
If all the settings above are as you expect, and the type is now how you expect it to be, Life should be good from here on out. The only downside is that you'll have to go back into your older documents and fix the anomalies. If they're not as you expect, you may be having problems with the font itself (rare, unexpected, but it happens).
- Close the document without saving, then go back to the Paragraph Styles panel with no InDesign documents open, and change the [Basic Paragraph] font from your Garamond 11 to a different font. At this point, we're just doing that for testing.
- Create a new document, lay down a line of type and see if it sets as you would expect it to be. If that font is working fine, it's safe to suspect that your Garamond 11 is corrupted. Delete the font from your system, get another copy of it — is it a Google font? — set the {Basic Paragraph] font back to Garamond 11 and try it again.
- If you get good results again, it's highly likely that your installed font got corrupted. If you get the same bad results again, it's highly possible that the Garamond 11 font itself is corrupted. In which case you might want to either get that font from somewhere else or just switch to a similar font that will work better for you.
Hope this helps. Please elt us know what did/didn't work for you, and the folks here will do our best to help you past your issues.
Randy