Do you have a metronome or use a click track? Slow it down and play along.
Does the singer have trouble with fitting in all the lyrics when the tempo is too fast? If so, you must either slow the tempo in order understand the lyric or have the singer practice better enunciation and diction.
We will vary the tempos of songs all the time for several reasons, to fit the lyrics, for the "feel", to make them more dance-able, etc, until we find just the right meter that works. Sometimes just a few clicks in bpm (beats per minute), up or down, can make a big difference.
Thank you for your indulgence,
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