Using an RUT240 with firmware 1.14.3 as a wireguard peer (client).
After a couple of issues the RUT240 was successfully configured as a peer and worked fine. I then changed the server to a different machine, and added a second peer config to the RUT240, and got that connected fine. As I didnt need the original peer config now, I attempted to delete it from the GUI, but got this error:
As suggested, I attempted to delete the luci-indexcache file from CLI but that didnt change anything.
I resolved the issue by using vi from CLI to edit etc/config/network to remove the peers configuration.
Note that I didnt factory reset the RUT240 and redo the config to confirm the issue, but may do if Teltonika cant replicate the problem.