PS Generative Fill error: We're experiencing delays due to high demand. Please try again later

What model did you use?

What sort of selection?

With a situation like below, I would use Gemimi 2.5 Nano Banana with a prompt like:

'Fix the tears in the cardboard box, and leave the rest of the box unchanged.'

The selection needs thinking about.  Selecting just the damaged areas is a mistake because that would not give NB enough context to work with, and you are likely to get a completely new box with a reasonably similar perspective. Using Select All is also risky because that can also lead to a completely new box.

NB will upload whatever selection you made, and turn it into a square the size of the longest size if you used the rectangular Marquee tool, or a square that encloses freehand selection made with the Lasso tool.  It won't use the information outside your selection.

Note: I also included 'and leave the rest of the box unchanged' in the prompt as a belt and braces attempt to restrain what was changed.

I am sure you know about the 1024 x 1024 resolution limit.  That comes into play with the size of your selection. So, if your image is 2000 x 2000 pixels, using Select All will compromise the resolution of the fix.   In that case keep your square box selection to 1024 x 1024 will ensure no loss of resolution.

If the image was more than 1024 x 1024 and you need to use Select All, then consider downsizing before using NB, and then use Genaritive Upscale to return to the original size.  

I am not sure about credit use for all plans, but with a full subscription all still image Ai tools have unlimited use.

One last tip — I am on a roll here 😉 — if you are using Generitive Fill to change a colour, then use it at full original resolution. Then change the blend mode of the Gen Fill layer to Color. This will retain the new colour information, but use the original layer's tone/contrast information making the fix fully sharp. 

we are experiencing delays due to high demands please try again later

This is what i get for like 10 hours now. 

I was on support twice for total of 7 hours as they tried to change every single possible setting on my computer as if something had out of nowhere changed on my end. They're having serious server issues if they cannot handle people using the tools they provide.
I'm experiencing it for the second time this week now. So incredibly frustrating. Making me want to jump off the adobe ship.