Where can i get my back tires fixed?

Check for a rock or thorn in the tire. Feel the inside of the tire carefully
There is some thing there that keeps poping the tube. Have fun. Be safe. Vern .

You may have a defective driveline U Joint, have them checked up on a rack by a tire shop, they work cheap or charge nothing for the inspection.

phil n ted tubes sadly are not covered by warranty my pram had all 4 tires do it including the new ones they said there was a batched of shonky tubes and sent me new ones as i kicked up a stink as it was only a few months old, but it did it again when we had a heat wave :( why not try buying a new tube and tire from a bike store the ones phil n ted supply are dodgy! and deflating it and puting the tire back on the rim wont work cos they tube seems to just buldge again when walking and pope the tire off and come off the rim. hope this helps its a well knowen problem that phil n ted couldnt be bothered fixing.

Do you have a tube it the tire? if you don't, pull the wheel off and lay in flat on the ground, put pressure around the tire at the rim edge and begin to pump with a compressor. A regular hand pump is hardly sufficient. You may even try standing on the tire edge while pumping if you can't get enough of pressure with the hands. The point is to push the tire inward to prevent air bypassing while pumping.

Could be tire pressure low. Put 35psi in them and drive for a few minutes to see if the light turned off.

While there is road side assistance that can help in times of need. It's imperative that every driver should know about how to replace a flat tyre. After ascertaining that the tyre is flat, you should check the link which will guide you to change the flat tyre with the spare one, have a look
=> DIY 10 easy steps to change flat tyre
=> How to Change Flat Tire

This sounds like tie rod ends are going out. Before you remove the old ones, mark on the threads where it currently is seated or you will throw it out of alingment when you put new ones on. You may need to borrow or buy the tool for poping out the tie rod end. They aren't a big deal to change if you have some basic tools and sometimes you don't need the wedge tool either. Once you get the old one out, try moving it around. If it is real loose and moves easily, thats your problem. But the swaying you are describing sound like this is the problem. Could be you steering control arms as well but because the inside of the tires are worn I doubt it.

Btw, I’m available to help over the phone in case u need at https://www.6ya.com/expert/matthew_d24b835e574ef6ca

make sure bead was poped on tire, also wheel bearings& bal on tire

If you have the capability to lift your tires using you cars jack try to rotate all tires at a time. make sure you have not engage to any gear anghand barke off and make sureto put a safety block on the opposite tire you are lifting. if you have hard time to rotating your tire wich is lifted and on nuetral positon your brakes are stuck. Have a good mechanic check it for you

Any bike shop will have patch equipment. You need to deflate the tire and remove it from the wheel. See if there is a tube inside the tire. If so, the fix is easy: either purchase a new tube for the tire, or get a patch. Use modelling glue on the patch then press it continually on the hole on the tire for about five minutes until it is dry. Afterwards, re-insert the tube into the tire, reattach the tire to the rim and pump it back up