Need to check if the date of the entry is within a period that is already locked

[pavulon18]

Describe the bug
Verify that the date that is being entered is not within a time period that is already locked. If it is locked, do not allow an entry by the user.

If it is locked by the user but not by the admin, then allow the admin to make changes. Any time an admin makes a change, the user needs to be notified.

If both the user and the admin have locked, then neither can make changes.

To Reproduce
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1. Go to '...'
2. Click on '....'
3. Scroll down to '....'
4. See error

Expected behavior
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Screenshots
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Desktop (please complete the following information):

• OS: [e.g. iOS]
• Browser [e.g. chrome, safari]
• Version [e.g. 22]

Smartphone (please complete the following information):

• Device: [e.g. iPhone6]
• OS: [e.g. iOS8.1]
• Browser [e.g. stock browser, safari]
• Version [e.g. 22]

Additional context
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