Could you please share a bit more about your issue?
Do you mean that your custom form created via PowerApps could not be loaded?
I have made a test on my side, and don't have the issue that you mentioned. The screenshot as below:
Please consider take a try to clear cache of your browser. then try it again, check if the issue is solved.
If the issue still exists, please consider remove the previous custom form from your SP list, then re-custom a new form for your SP list using PowerApps, then try it again, check if the issue has been fixed.
More details about removing custom form from SP list, please check the following article: