What version of android is running on the smartphone? If it’s lower than 4.4 you have to install the legacy version (which supports android versions from 4.1).
However, not being a support forum for newpipe to get an answer you should check directly the issues in the github repository of newpipe legacy (Issues - TeamNewPipe/NewPipe-legacy - Issues · TeamNewPipe/NewPipe-legacy · GitHub) and see if your problem has already been reported in case it has not been reported you can report it by opening an issue and providing as many details as possible.