Seat post Slipping :(

My issue lately is my seat post slipping while Im riding. Tube size is 25.4 and the seat pin is already tightened to its limit. Any suggestions? I wrapped it with a teflon tape for first aid. Should i buy a new seat post? It's an alloy one and I've just used it for weeks.

Probably your bolt / clamp. Take it to LBS. they can sort it

or the seat tube on the frame needs reaming

I'll try but it think its the frame itself that's worn out :<

Is the seatpost the correct size? The clamp bottoming-out suggests it isn't. As does being able to wrap it in tape and still get it in.

And assembly paste (not to be confused with anti-theft paste) is the preferred method to prevent correctly fitting seatposts slipping, not tape.

Grit yo shit to turn security paste to assembly paste

Don't you have livestock for that?

Dredge...

I have a carbon post in a Ti frame that had not slipped position in 5 years.
It's now driving me mad... have tried carbon ass paste, any other suggestions?

A better clamp?

What we use in stubborn cases, and there's plenty of this with new proprietary bullshit clamps, d-shaped seatposts and out of tolerance frames is hairspray. But better be sure where do you want it because breaking the bond takes a lot of WD40 and swearing.
Better if you can try different seatposts and clamps, tolerances in the bike industry are so bad you may find something that works.

Great advice - Might try a new clamp.
Have dealt with a stuck post in the past and that's a road I really don't want to go down!