my app has been created with electron-forge and I got this error during electron startup:

App threw an error during load
Error: Cannot find module 'ajv-formats'
    at webpackMissingModule (F:\git\teacher_e-iac_encrypted\.webpack\main\index.js:6530:87)
    at Object.<anonymous> (F:\git\teacher_e-iac_encrypted\.webpack\main\index.js:6530:173)
    at Object../node_modules/conf/dist/source/index.js (F:\git\teacher_e-iac_encrypted\.webpack\main\index.js:6980:30)
    at __webpack_require__ (F:\git\teacher_e-iac_encrypted\.webpack\main\index.js:21:30)
    at Object../node_modules/electron-store/index.js (F:\git\teacher_e-iac_encrypted\.webpack\main\index.js:8141:14)
    at __webpack_require__ (F:\git\teacher_e-iac_encrypted\.webpack\main\index.js:21:30)
    at Object../src/util/db-util.ts (F:\git\teacher_e-iac_encrypted\.webpack\main\index.js:14092:40)
    at __webpack_require__ (F:\git\teacher_e-iac_encrypted\.webpack\main\index.js:21:30)
    at Object../src/main.ts (F:\git\teacher_e-iac_encrypted\.webpack\main\index.js:14026:17)
    at __webpack_require__ (F:\git\teacher_e-iac_encrypted\.webpack\main\index.js:21:30)

------------update-----------
looks like the problem is related to yarn
I run my app with npm and it fixed but I had this problem with yarn and yarn.lock