Convert decimal number AS SEEN to mm:ss

Maybe this will help
Decimal time in A1. Enter in B1 and format as mm:ss

Formula:

=(1/86400)*(--LEFT(A1,FIND(".",A1)-1)*60+(--RIGHT(A1,2)))

To return a maximum of 59:59 format as mm:ss

Formula:

=MIN((1/86400)*(--LEFT(A1,FIND(".",A1)-1)*60+(--RIGHT(A1,2))),0.04165)

If you want 0 returned if greater than 59:59

Formula:

=IF((1/86400)*(--LEFT(A2,FIND(".",A2)-1)*60+(--RIGHT(A2,2)))>0.04165,0,1/86400)*(--LEFT(A2,FIND(".",A2)-1)*60+(--RIGHT(A2,2)))