By default wordpress uses php mail() function which often is the reason why mails go to Spam folder. To avoid this you can make a bit more advanced mail setup for prevent emails go to spam folder
1. Install “WP MAIL SMTP” plugin
2. Activate the plugin
3. left sidebar and click “WP Email SMTP”
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we will show you how to use Gmail account via SMPT
Go to setting in WP Mail SMTP and choose Mailer to other SMTP
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Log into your Gmail account and set option “Let less secure apps use your account”. How to do it you can find in this article: https://support.google.com/accounts/answer/6010255?hl=en
Configure settings for prevent emails go to spam folder
SMTP Host: smtp.gmail.com
SMTP Port: 465
Encryption: Use SSL encryption.
Username: your full Gmail address ( xxxx@gmail.com)
Password: your Gmail password
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Save Setting and send test email
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