‘And Joshua burnt Ai, and made it a heap (a mound - ‘tel') for ever, even a desolation to this day.'
This must have been written before the later restoration of Ai which, if the usual site is accepted, was in the time of the Judges. But it was not even then restored as a walled city. The much later city was probably built elsewhere (Isaiah 10:28; Ezra 2:28). So the great battle of Ai was over with victory going to YHWH. There is no further mention of Bethel. That city was probably not taken which is why it was not mentioned. But it would be militarily weak for a long time to come. Its king was slain by Israel later on (Joshua 12:16).