I am writing a simple game in ez80 assembly, and every single time I run the program, my calculator's free RAM goes down a lot.
I can run the game maybe 4-5 times before it runs out and a memory error occurs.

Is my program simply not deallocated from memory, if so, how do I get it to?

I added double buffering into my program, as before you could see it rendering visually and flickering.
But now with double buffering, half of the screen flickers (not exactly half, I can't find a pattern, but it's mostly pixels at the bottom), and it now takes around half a second to render, before the buffers are swapped again.
I'm assuming this is because we wait for the interrupt, but it still seems to be very long.

call SJQ_setgraphics
loop:
; Simple buffer cleaning, sets everything to 0.
ld HL, (SJQ_curbuf)
ld (HL), 0
ld DE, (SJQ_curbuf)
inc DE
ld BC, 320 * 240 - 1
ldir

; do some more drawing here.

call SJQ_bufswap

SJQ_setgraphics:
; Sets the palette.
ld HL, SJQ_PALETTE
ld DE, $E30200
ld BC, SJQ_PALETTE_END - SJQ_PALETTE
ldir
; Enables 8bpp.
ld A, $27
ld ($E30018), A
; Sets up double buffering.
ld HL, vRam
ld (mpLcdBase), HL
ld hl, vRam + 320 * 240
ld (SJQ_curbuf), HL
ld HL, mpLcdImsc
ld (HL), 4
ret

SJQ_bufswap:
ld HL, (SJQ_curbuf)
ld DE, (mpLcdBase)
ld (SJQ_curbuf), DE
ld (mpLcdBase), HL
_:
ld HL, mpLcdIcr
set 2, (HL)
ld HL, mpLcdRis
_:
bit 2, (HL)
jr Z, -_
ret

SJQ_bufwap, the third third of SJQ_setgraphics are all that work on the double buffering, of course I found little docs on the internet (searching stuff like 'double buffering ti', or using exact matching, etc).