Unexpected garbage pixels in logo demo for Amstrad CPC emulator

Question

I'm "emulating" the Nintendo Gameboy logo demo in an Amstrad CPC Emulator (WinApe) in mode video 1, encoded in assembly for the Z80.

When I "paint" only the logo (until the line 25 and comment the others lines in main loop), It paints good, but when I try to create the animation (paint, erase, paint, etc.), appears some "garbage" pixels not painted previously.

This is my code:

;; testlogo.asm
;;
.cls    equ &BC14   ;; Clear screen
org &4000
run &4000
;;
call cls
ld hl, #c020        ;; initial position of video
ld a,#05        ;; times logo down      
call loop1      ;; call main loop
jr $
;;
loop1:
   ld bc,logo       ;; initial position of logo
                    ;; bc remains until logo
                    ;; is fully painted
   ld e,#08
   call loop_paint
   ld de, #c050
   add hl,de
                    ;; the second 8 row group pixels
   ld e,#08
   call loop_paint
   ld de,#c050
   add hl,de
                    ;; wait until 'down' logo
   ld b,#cc
   call wait
   ld de, #ff60     ;; recover hl position 
                    ;; to 'erase' upward logo
   add hl,de
   ld e,#08
   call loop_erase1 ;; call to 'erase' pixels
                    ;; from logo
                    ;; (it could be optimized in one calling)
   ld de, #c050
   add hl,de
   ld e,#08
   call loop_erase1
   ld de, #c050
   add hl,de
   dec a
jr nz, loop1
ret
;;
loop_paint:
   ld d,#0b
   call loop_logo   ;; call to paint logo
   push bc          ;; save bc in stack
                    ;; for using adding in bc
   ld bc,#07f5      ;; 800 for next row (minus) 0b last column
   add hl,bc
   pop bc 
   dec e
jr nz, loop_paint
ret
;;
loop_logo:          ;; finally 'paints' logo
                    ;; in memory video
   push af          ;; save 'a' register
                    ;; because is used
                    ;; as counter in main loop
   ld a, (bc)
   ld (hl), a
   pop af
   inc l
   inc c
   dec d
jr nz,loop_logo
ret
;;
loop_erase1:        ;; row by row in mode 1 video
   ld d,#0b     
   call loop_erase2
   ld bc,#07f5      ;;800 next row - 0b last column
   add hl,bc
   dec e
jr nz,loop_erase1
ret
;;
loop_erase2:        ;; column by column in mode 1 video
   ld (hl), #00 
   inc l
   dec d
jr nz,loop_erase2
ret
;;
logo:
db #00, #00, #00, #00, #00, #00, #00, #00, #00, #00, #00
db #00, #00, #00, #00, #00, #00, #00, #00, #00, #00, #00
db #00, #FF, #FF, #FF, #FF, #FF, #FF, #FF, #FF, #88, #00
db #33, #FF, #FF, #FF, #FF, #FF, #FF, #FF, #FF, #EE, #00
db #33, #F0, #F0, #F0, #F0, #F0, #F0, #F0, #F0, #E6, #00
db #FC, #F0, #F0, #F0, #F0, #F0, #F0, #F0, #F0, #F1, #88
db #FD, #F5, #FB, #F5, #FE, #FF, #F3, #F3, #FB, #FD, #88
db #FD, #F9, #FB, #FD, #F0, #F8, #F4, #FA, #F1, #F1, #88
db #FD, #F1, #FA, #FD, #F6, #FF, #F4, #FB, #F9, #F1, #88
db #FD, #F9, #FA, #F5, #F2, #F1, #F4, #FA, #F1, #F1, #88
db #FD, #F5, #FA, #F5, #FE, #FF, #F3, #F2, #F1, #F1, #88
db #FC, #F0, #F0, #F0, #F0, #F0, #F0, #F0, #F0, #F1, #88
db #33, #F0, #F0, #F0, #F0, #F0, #F0, #F0, #F0, #E6, #00
db #33, #FF, #FF, #FF, #FF, #FF, #FF, #FF, #FF, #EE, #00
db #00, #FF, #FF, #FF, #FF, #FF, #FF, #FF, #FF, #88, #00
db #00, #00, #00, #00, #00, #00, #00, #00, #00, #00, #00
ret
;;
wait:
  halt
  dec b
jr nz,wait
ret

And this is the result in the emulator window:

Last line of logo must be in red only and no contains another color, logo is in red and yellow.

Answer 1

Problem was resolved when I change from 8 to 16-bit increments for the pointers: "inc l" for "inc hl", "inc c" for "inc bc".

Thanks to "the busybee" user.