fal·ter
ˈfôltər/
verb
1. start to lose strength or momentum.
"her smile faltered and then faded"
synonyms: hesitate, delay, drag one's feet, stall; waver, vacillate, waffle, be indecisive, be irresolute, blow hot and cold, hem and haw; informal sit on the fence, dilly-dally, shilly-shally
2. speak in a hesitant or unsteady voice.
""I c-c-can't," he faltered"
synonyms: stammer, stutter, stumble; hesitate, flounder
3. move unsteadily or in a way that shows lack of confidence.
"he faltered and finally stopped in midstride"
synonyms: struggle, stumble, flounder, founder, be in difficulty