Royal Cheese outdoors

Probably teh intensity of light, but i wouldn't overreact. I see some spacing between growth nodes, so it isns't extreme in nature. If growth nodes do not 'stretch' out in a good way, reduce light a bit.. maybe shade it for an hours or but a netting over it might block enough light throughout the day. Also, in future use soil with better drainage properties. That looks like mostly clay and other compacted material, which won't be good for optimal growth rates. perlite, vermiculite, leca balls (hydroton), even tiny wood chips if nothing else etc etc... a 50/50 mix is great, but maybe in that sun you might want a higher soil ratio with increased evaporation occurring. If soil is heavy in clay, maybe a bit more drainage heavy... Don't expect good growth till they get some girth on those leaves... then it will speed up quickly. They aren't as slow as you likely feel. So, i think this is just a case of slightly too much light too early, So, reduce it a bit, but expect teh plant to be more robust shortly... The length of internods is key to recognizing it wants more... they will lengthen to reach for light when not getting enough... when getting too much they remain short. In extreme cases it will look like the leaves of multiple growth nodes are popping out of same spot on stem. Some stretch is good. Too much stretch causes instability. Observe and react.

What did you do since the last question? It looks like it grew from week 3 to week 4 in your diary. If you have made some changes, i'd see them through. Vigorous growth will not resume overnight. It will more likely be a slow march back up to full speed. if those nodes at top stay bunched up together as it continues to add new nodes, it's too much light as the cause. Must observe to know for certain. This will be overtly obvious if true. Autoflower's ruderalis genetics come from Northern hemisphere with short days for most of the year, hence they evolved to not react to long nights to cause bloom phase to start. They are not as robust to the heat and light intensity as a strain that comes from the tropics. Interbreeding and such makes this more difficult to associate any traits based on region of origin. In the end, it could also just be a runt. While it can happen to any strain, it happens more often with autoflowers. The leaves look healthy enough with some minor stress signs likely related to heat. I think i said it before.. get something that cuts the lgiht down... or shade the plant for a few hours per day and see what happens over 5-7 days. A mosquito gaurd type material might be perfect for all day long that still lets in majority of light.

My opinion is that your soil is too compacted and because of this the roots do not have enough oxygen and cannot breathe, when preparing the soil always mix it with 30% perlite and use only specific and recommended soil for cultivation.

Only chance would be to graft it back on. Get a sharp knife and cleanly cut the stem then quickly after you want to cleanly cut the "stump" sticking out of the ground. Once both are cut stick the cut ends together and wrap with medical tape. Then add a stick to brace the break and wrap again. After 2-3 days you can inspect and unwrap. But this was at least 1h ago, Not sure how long you would have to do the above and be successful. If done in the first 10 min you would have a good chance.