There is no way to stop this from happening, unless you edited the exchange rate and set it manually. You can do this by going to the cog wheel, account & settings, advanced and then manage currencies. Here you can select edit.
Thanks for your suggestion
I did exactly as you detailed here however, the following day it was reset again. Manually changing on a daily basis is not an option and we were told prior to migrating to QBO that the auto-update feature could be turned off
Hello there, Rob,
I appreciate you manually editing the exchange rate as an alternative method to help stop its automatic update.
There isn't currently a way to turn this feature off once turned on. I'd still suggest manually changing the exchange rate on a daily basis.
I'm including these articles below to learn more about how multi-currency works in the program:
I'm here anytime you need further assistance. Have a good day, Rob.