Error in build : Invalid register: v16. Must be between v0 and v15, inclusive.

[AS L]

HI All , 

I encountered the following errors when i add in some codes to invoke a method. I have also inserted the same codes into other files which did not  have errors. 

I have search the codes , there are no register bigger than v15 being used. 

Error 

decompile\smali\org\w.smali[5583,0] Invalid register: v16. Must be between v0 and v15, inclusive.
decompile\smali\org\w.smali[5607,0] Invalid register: v16. Must be between v0 and v15, inclusive.
decompile\smali\org\w.smali[5619,0] Invalid register: v16. Must be between v0 and v15, inclusive.

codes i inserted is highlighted in yellow.

   .locals 16

    const-string v1, "asdd3RGa"

    invoke-virtual {p0, v1}, Lorg/org/w.smali;->decrypt(Ljava/lang/String;)Ljava/lang/String;

    move-result-object v1

    const/4 v2, 0x1

    invoke-static {v2}, Ljava/lang/Boolean;->valueOf(Z)Ljava/lang/Boolean;

    move-result-object v2

Any suggestions thanks.