Bug or my fault? (types related)

I use the for each because if i don't all the field type return me the error" variable musty be a type" or "object don't exist" if i try to process some field type inside other function.
I don't understand what do you mean for different variable name....i use jet.mainjet because jet.mainjet is the type instance....if i use,for example,this_jet.mainjet=each mainjet....if i try to access type field inside other function...i get a "object doesn't exist" error...because i don't have declared global the instance of this_jet.mainjet
Now i write some code to see if you tell me (if you want of course!) what the error is.
In this function i use 3 calls to millisecs() in a row....so if i take the same code in a function don't work....if i take the EXACT code in the main...work!

Function prova()
	

	For jet.main_jet=each main_jet
		
		assex=JoyX()*2
		assey=JoyY()*2
		joypad=JoyX()
		jet\posizionex=jet\posizionex+assex
		jet\posizioney=jet\posizioney+assey
		If jet\posizionex => 630 Then jet\posizionex=jet\posizionex-2
		If jet\posizionex <= 10 Then jet\posizionex=jet\posizionex+2
		;x=x+assex
		;y=y+assey
		;If x => 630 Then x=x-2
		;If x <= 10 Then x=x+2
		If startmov=0 Then fotogramma2=3
		
		If joypad=0 And startmov=1	;no left or right direction pulled and no animation started
			If orologio > counter+50
				counter=orologio
				If fotogramma2 > 3
					current_frame=fotogramma2
					fotogramma2=current_frame-1
					If fotogramma2=3
						fotogramma2=3
						startmov=0	;reset the anim to not started...
					EndIf
				EndIf
				If fotogramma2 < 3
					current_frame=fotogramma2
					fotogramma2=current_frame+1
					If fotogramma2=3 
						fotogramma2=3
						startmov=0	;reset the anim to not started...
					EndIf
				EndIf
			EndIf
		EndIf

		If joypad=1 Then 	;if joypad pull right
			startmov=1
			If orologio > timer + 150
				timer=orologio
				current_frame=fotogramma2
				fotogramma2=current_frame+1
				If fotogramma2 => 6 Then fotogramma2=6
			EndIf
		EndIf

		If joypad=-1 Then	;if joypad pull left
			startmov=1
			If orologio > timer2 + 150
				timer2=orologio
				current_frame=fotogramma2
				fotogramma2=current_frame-1
				If fotogramma2 < 0 Then fotogramma2=0
			EndIf
		EndIf
		;For jet.main_jet = Each main_jet
			If jet\resistenza <= 0 
				crea_esplosione(jet\posizionex,jet\posizioney)
				Delete jet
				jetdistrutto=True
		Exit
			EndIf
		;Next
		DrawImage(jet_image,jet\posizionex,jet\posizioney,fotogramma2)
		jet_collisionx=jet\posizionex
		jet_collisiony=jet\posizioney
		DebugLog fotogramma2
		DebugLog timer
		DebugLog counter
		DebugLog startmov
		DebugLog orologio
	Next
	
	
	
End Function

Orologio is declared global at the start of the code.