How to block a user's email address?

Registration date
Wednesday June 19, 2019
Last seen
September 30, 2019
Hello and respect!

I ask the members of this nice forum to help me!
I opened an email account and only me, I know the right one (main password). I am in charge of that email account.
Last year, I asked you how our Hunters who have cameras mounted in the forest can use it and they all send pictures via this email of mine.
They just want to send pictures via my email so I can view their pictures and they can also get them on their emails.
These are hunting cameras that go over the phone SIM card where this (joint) email should be put first
because it is through my email that pictures are sent to their private emails. I hope you understand me...

My email is: and I have my password where I can enter my account, I can delete, I can change etc ...

Then I asked Google to give me some code where more people (our hunters) can use my email (but it can't modify or delete anything from it).
This is this code: rpufzxemojozyoyw

I'm very happy because it works beautifully, me and my hunters are pleased. Their cameras work beautifully!
Please do not block or delete this account because we are all happy for the conservation of forests and animals ...

This is how their cameras look and their hunting camera settings:

Their hunting pictures can be seen by me and them. This has been working very well for a year now.
The problem is that our hunters gave other hunters this email with our shared code, and now some other hunters put their email in their cameras.
I do not want to receive pictures from other hunters other than ours.
I can see all their emails from where the images to my account from "SENT"

My main question is: How can I block some email addresses so I can no longer use my email?
I mark with "JUNK" but you do not block them still and they can also send their pictures from the forest every day via my email.

There must be a way that I can block those emails that are not ours and I don't want them to use my account?
We are very happy to use this email ... but just that there is some solution
that I can block some of his emails from getting pictures that are not from our hunters? Explain to me exactly what to do!

THANK YOU from the heart and hope you understand my request and help me!
Thanks in advance!
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