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Firstly consider stopping using soap, it's as bad for hair if not worse than sulphates. Vinegar will reset the pH and chelate but is not a replacement for conditioner
Porosity and Curly Hair
The Scoop on Vinegar

Leave in is shortform for leave in conditioner. None the products you list as using are conditioners - a 'true' conditioner is rich in the major emollients (cationic surfactants and fatty alcohols). Many of us use our rinse out as a leave in as well, but your detangler again is not a 'true' conditioner. Fine hair tends to do well with hydrolysed protein, it tends not to do well with heavy ingredients that can build up like shea butter and waxes.
Ingredients Commonly Found in Hair Care Products
Science-y Hair Blog: Product List By Category

Flaxseed gel can last a couple of months if you use sterile technique and a preservative. Otherwise you can purchase it from Sweet Curls Elixirs on Etsy, or try Jessicurl Rockin Ringlets. Both hydrolysed protein and the epsom salts (magnesium sulphate) in RR are curl boosters.
http://science-yhairblog.blogspot.co...-projects.html
http://science-yhairblog.blogspot.co...=preservatives

In dry climates/ low dew points humectants like glycerin, propylene glycol, honey and to a lesser extent aloe vera can draw water out of the hair, especially a problem for more porous hair. You have aloe in both your styler and your detangler.

HTH.
2a-2c, medium texture, porous/ colour treated. Three years CG. Past bra strap length heading for waist.

CO-wash: Inecto coconut/ Elvive Volume Collagen
Treatments: Komaza Care Matani, coconut/ sweet almond/ fractionated coconut oils, Hairveda Sitrinillah
Leave in: Fructis Sleek & Shine (old), Gliss Ultimate Volume, various Elvive
Styler: Umberto Giannini jelly, Au Naturale styling gelee
Flour sack towel, pixie diffuse or air dry.
Experimenting with: benign neglect