Easy but how? 802.3ad bonding - 2 wans & 2 mkt routers

Complete beginner here,
Simple question for what I think should be a simple setup:
I want to “802.3ad bond” the signal from 2 T-mobile phones that hotspot to 2 mikrotik routers (both hap lite tc on station pseudobridge mode). A final generic router will relay the bonded signal to my smart TV.

Current setup:
Mkt1: hotspotA was scanned & received by wlanA (sent out eth3 bc they’re both on bridgeA), connected with ethernet cord to Mkt2’s eth3.

Mkt2: hotspotB was scanned & received by wlanB (sent out of eth1 bc they’re both on bridgeB). An ethernet cord connects eth1 to eth2, so both hotspotted internets come in via ethernet ports eth2 (hotspotB) & eth3 (hotspotA) - I thought this was important for bonding. Signal from bonding1 (slaves: eth2 & eth3) is sent out eth4 bc they’re both on bridgeC.

I have no IP addresses set up & NAT is on interfaces bridgeA, bridgeB.
Problem: only 1 hotspotted signal is used, based on traffic (traffic from Mkt2 eth3 is nil, AKA hotspotA goes unused OR traffic from eth1 & 2 is nil, AKA hotspotB goes unused).

Same results from similar setup:
Sending bonded signal from Mkt2 eth4 to Mkt1 eth1 (then sent out eth4 bc they’re both on bridgeD) & NAT only on Mkt1 eth1, no NAT on Mkt2.


I don’t know anything about all the MANY mikrotik settings available, but I thought it’d be easier to get this simple idea to work: 802.3ad bonding of 2 internet signals to get double internet speed? Is there some IP address or vlan settings I’m supposed to use? Weeks of effort & no pay out yet…What am I missing?
Thanks
P.S. I’ve been testing the signal directly from mikrotiks to my PC, so the final router isn’t an issue.