I have a Companies worksheet and a Contacts worksheet. Within the contacts sheet, I have a column with companies and then contacts. There are multiple contacts at each company and thus, duplicate instances of each company in the companies column. I am attempting to insert the contacts at each company in one cell under the Companies worksheet.

I originally got this to work by inserting a helper column under the contacts worksheet that inserted the company name plus the number of times it occurred previously in the list... =B4&COUNTIF($B$2:B4,B4) and then using =VLOOKUP(companyname&1,range:range,column,FALSE)&" / "&VLOOKUP(companyname&2,range:range,column,FALSE)etc... This currently works as long as I have the same amount of vlookups in my formula as there are companies available in the contact sheet, the issue is that it's not automated. In other words, if the company currently has 3 additional contacts and I add the vlookups together 3 times, it works, but once I add an additional contact, I have to update the formula to include another vlookup function. Alternatively, if I delete a contact, the formula then produces an error because the 3rd result no longer exists and thus, I have to edit my formula.

IE:
A / B / C
Walmart1 / Walmart / Joe
Target1 / Target / Sue
Walmart2 / Walmart / Jack
Walmart3 / Walmart / John

Formula for single cell: =VLOOKUP(walmart&1,$A$1:$C$4,3,FALSE)&" / "&VLOOKUP(walmart&2,$A$1:$C$4,3,FALSE)&" / "&VLOOKUP(walmart&3,$A$1:$C$4,3,FALSE)
Result for single cell: Joe / Jack / John

Can anybody suggest a better method that prevents me from having to update my formula every time I update the contacts worksheet?