Lost all charts and tabs

Lost all charts and tabs. Made fatal error.
How do I retrieve BOTH please?

These solutions unfortunately not helping.
The current tabs, which I hardly need, are Sheet 1, Sheet 2 ... to Sheet 23.
When I apply File - New - Default Chart, the result is more charts with the above tabs, but not the tabs that I have lost.

You might consider providing a screenshot, as nobody knows what you see on screen without you providing that info as a picture, not words.

Consider also explaining what is your GOAL and what "tabs" you need because there are MDI tabs and chart sheets which are different thing.

Again, screenshots (pictures) are worth 1000 of words.
Please follow this advice: How to ask a good question

Thank you Tomasz,
Below please find 1000 words.
The chart sheets I've lost have all my specific indicators on each chart/sheet. All gone. Of course I can still ADD new indicators.
The tabs have also disappeared. Remaining are those that I rarely use Sheet 1, Sheet 2 ..etc
I've since rebuilt 2 tabs, CHANNELS and BASIC CHART.

Once again thanks for your help.

It is still unclear what you had before you "lost", but really nothing is really "lost". You might have just closed the pane / window.
If you did and FIle->New->Default Chart does not open your last setup (it usually does), then you still got all formulas in "Formulas" subfolder.
You might also just restore backup. You do have backup don't you?

You might also just restore LAYOUT files (in the "Layout" subfolder)