SOTA scoring is based on honesty and not on proof of QSO. The chaser will get the points if they log a QSO with you irrespective of whether you enter a log. There are undisclosed checks and safeguards to winkle out those who are tempted to cheat.
Yes, that is why there is a facility to delete a log.
We do not provide an edit facility as the effort to do so it not worth it. We would need to ensure that edits do not corrupt the database integrity, can cope with interruptions to user connections and discourage frivolous edits, never mind people editing the wrong activation etc. We do provide facilites that make the end result easy.
If you uploaded a CSV or ADIF log, you can edit/regenerate your CSV/ADIF file, delete the log you uploaded and upload the corrected log. If you manually entered the information, you can download the log in CSV format, edit the CSV file, delete the log you uploaded and upload the corrected log. Once you have performed this once or twice it is trivial and errors can be fixed in very little time.
You can edit CSV files in either a text editor (not word processor) or using a spreadsheet program. LibreOffice is a free open source equivalent to MS Office and is available for Windows, Linux and OSX if you do not have anything suitable.
You should take note that CSV/ADIF log upload now allows you to upload activation logs, S2S logs and chaser logs in one go. This means that if you uploaded a log that contained activation(s) and S2S logs and you wish to delete and reupload the activation content you will have to delete all the activation and S2S logs in that file or you will get errors. Despite the errors being highlighted in red and a “duplicate entry” warning appearing, this does confuse people still.
The Manage Uploads menu item exists to simplify re-uploading logs. If you use it the it will show you all the uploads you have performed (since May 2020 ISTR) and for each upload, how many activation, S2S and chase QSOs were uploaded. If you still have the CSV/ADIF you used, you can use the manage upload delete function to delete everything you uploaded in any CSV/ADIF file. You can then edit/regenerate the file, reupload and it’s job done where you can reward yourself with a nice cake/biscuit/beer/whisky/tequila/joint/speedball/nose-candy or fix… whatever is your poison 
Seriously, it’s straightforward once you have done it once or twice and there should never be a need to re-enter all the QSOs by hand. You can practice if you want by entering a fake activation etc. and downloading/editing/reuploading. Just remember to delete your practice entries.
If you need more help, just ask.