Error 404 wp-admin and wp-login

Hello,

I start the creation of a new site, I install the WPS Hide Login plugin but it doesn’t work correctly, one time it works, one time it’s error 404.

Since I’m starting the site, I have few plugins installed, except WPS Hide Login, so I have the following installed: Cache Enabler, Fast Velocity Minify, Protection Against DDoS and Really Simple SSL.

I have the default WordPress Twenty Nineteen theme.

I just have my .htaccess which is customized.

I have already disabled all plugins and now I have access to my WordPress administration all the time.
I have already changed the autenthification keys in wp-config.
I have already changed the permalinks several times.

Thanks in advance for your help.
Mickaël

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