Memory allocation issue

Hey there,

i just installed the plugin, when i went to the backend page to adjust a username, i got an error 500. Log states:

Allowed memory size of 268435456 bytes exhausted (tried to allocate 2031616 bytes)

Using flywheel as a host, might this be caused by the number of users in the db (about 12.000) I also saw a memory exhaust error for Postman plugin, you plugin doesn`t trigger any email sending when approaching the username asjust page right?