Hey there greenmind,
Thanks for stopping by the Apple Support Communities! It sounds like you're having some issues removing a repeating event from your iCloud Calendar. I know that I like to keep myself organized by using the Calendar feature. I have a few ideas for you on how to remove that event for good.
Let's start by making sure that you did in fact delete the first event in the repeated series. This would involve knowing the precise month, day, and year that you created the event on. After that, we're going to try simply force quitting the Calendar app on your iPod, and then restarting your device. After it turns back on, check to see if the event is still showing up. The following articles will walk you through this process:
Force an app to close on your iPhone, iPad, or iPod touch
Restart your iPhone, iPad, or iPod touch
If the event has not been removed, the next step will be to turn off the calendar syncing feature in iCloud. You'll want to do this on all of your devices that are connected to iCloud. Go to Settings > iCloud. Find "Calendars" and tap on the toggle switch to turn off syncing. Repeat on each device. After you've turned off Calendars on all your iCloud-enabled devices, restart them. When they're back up and running, re-enable "Calendars" within iCloud settings again, and check on the event.
Prior to completing the next step, we'll want to ensure you have a recent backup of your iPod touch. Here's a helpful article on how to create a backup:
How to back up your iPhone, iPad, and iPod touch
Next up would be to sign out of iCloud completely on all your devices. For iOS devices, go to Settings > iCloud. Scroll to the bottom of the screen and tap on Sign Out. You'll be asked if you want to keep or delete your iCloud data. To be safe, tap on keep. Repeat this process on each iOS device. If you use iCloud on a computer, you'll want to go into either System Preferences > iCloud on a Mac, or open the iCloud app on your PC. You'll be able to sign out in either location. After signing out on all devices, restart each one, then sign back in. Check to see if the event has been permanently deleted.
Another great step if we're still running into issues is to reset the settings on your iPod touch. This will not remove any of your personal data (e.g. pictures, apps), but you will need to adjust specific user settings. This could include wallpaper, ringtones, etc. Do also make sure that you have your Wi-Fi network names and passwords available, as this removes your remembered networks. Go to Settings > General > Reset > Reset All Settings. After your iPod restarts, check the Calendar app for the event.
Finally, we can have you restore your iPod to factory settings. This will install a fresh copy of iOS on your device, which helps to rule out any software issues. After the device has been set up as new, you can log in to iCloud and check on that repeating event. If it's gone, you can restore from your backup, and then make sure the backup hasn't brought the event back with it. These articles provide the necessary steps:
Use iTunes on your Mac or PC to restore your iPhone, iPad, or iPod to factory settings
Restore your iPhone, iPad, or iPod touch from a backup
Have a wonderful day!